Partykof

Netapp FAS or IBM N-Series, this is the question?

2011-03-26T11:24:00.006+02:00

Around this April, IBM is finally about to announce their equivalents to the FAS3270 in N-Series. This raises the question again, which is better to acquire?

I've used them both and have seen advantages to both platforms. Beside the late bloom of the N-series equivalent of the FAS and it's derivatives, there is the issue of support, which is provided by Netapp engineers. But the most troubling issue, is related to IBM's commitment to N-series in the next few years with their Storwize product line.

On every recent session I had with IBM, the V7000 storage system is offered first. The latter product line is aimed at Mid-Range Disk systems, just as the N-series was positioned so far. When I point out that SAN environment is a must then the XIV product line is suggested.

To my honest opinion, it seems that IBM is keeping N-series customers on low fire, just till they have a better solution for this SMB, Mid range market.

For someone who is an IBM customer for many years, it seems unfair – On one side show commitment to the N-Series by introducing new products, on the other side, develop and strongly market their in house alternative. Maybe it is Netapp who should raise this question on behalf of the customers and ask IBM to share their 5-Year roadmap vision of both product lines, so we as customers should know what to choose at this point in time.

What is your insight? - You are welcome to leave your opinion on the comments below.

-Partykof

Mobile devices - The backdoor to your enterprise

2010-12-15T20:11:00.002+02:00

In the past years, mobile devices and smartphones in particular have presented a new threat to the leakage of information from the organization. The CEO's iPhone was lost and his emails are now exposed to the world, or maybe worse, the Sysadmin's blackberry with some passwords or other important data was stolen. Well, there are many ways that can help you assist minimize the risk by remotely revoking or erasing the device, and I am not going to discuss those.
The huge install base of the iPhone and Android devices is very appealing to hostile entities who wish to penetrate your organization's shield and retrieve information or maybe just damage it. Be it Cybercrime criminal or Cyberwar soldiers, these mobile devices have become their gateway to your fortress, and they are not that protected.
Apple offers the iTunes store where you can download thousands of applications for your iPhone. Are these apps secured, well, some are, and most of them are really harmful, well let's just say for the sake of the discussion they are.
Google offers a huge Market place for Android applications, developed under the umbrella of the open source community, which allows a variety of apps which anyone can develop. Are these apps verified as secured, well they might be, but then again their not really checked, not each and every one.
Let's take a simple scenario where an app is checked and it seems secured. But if someone creates two apps that each on its own, is harmful, but when put together on the same device can become hole for the dropper. The dropper, is a payload carrier for hackers to put any kind of code they wish to hijack your device to their needs.
The problem becomes very clear, when you jailbreak an iPhone, in that case, the jailbreak application or its process can leave a hole for that same purpose. It might be later, when you download a cracked app that you can find on Cydia, or maybe the one you downloaded from a torrent site somewhere, can be this mobile Trojan horse.
The next stage will be for this Trojan to collect your stored credentials to gain access to your corporate network, or maybe to place another dropper that will place a Trojan the minute you plug your iPhone to your computer, and their in.

For now there is no real way to identify a jailbreak iPhone remotely, since Apple cannot keep up with the ones who develop it. Some even say that they are silently dropping the SDK that was used for that, which other companies used to develop product that would block it.
There is not much to do around that except be smart. Here are some tips I could think of that might assist in this situation, at least until someone comes up with a solid solution.

Communicate and educate users about these threats, so they will be aware of the consequences.
Set a policy that allows only iPhones that have not gone through the jailbreak process to be connected to your servers.
Consider using an anti-virus application on your mobile devices.
Recommend that the iPhone will be used for business purposes only – well, as much as possible.
Enforce password access to unlock these devices.
Purchase and install certified apps only.
Make sure you can remotely disable and wipe the device in case it was lost or stolen.

I guess there are many more that others could think of. If any comes to your mind, you can leave a comment or maybe send me a note and I will include them.

Be safe.
Partykof

Naming conventions in IT environment

2010-12-03T21:19:00.008+02:00

This post is intended to provide a common set of guidelines useful when handling large number of records in your IT environment, records such as usernames, computer names, devices and other records, by applying some naming convention to these records and explaining the standard settings that will help others understand these conventions and schema. One common way of differentiation between elements is using suffix names, that is if your environment spreads across multiple countries or domain names. The scope of post is related to prefix differentiation which is a problem in local environments or databases.

Not much attention is given to naming convention in the IT environment, especially when starting out small. I remember my first network carried out names of characters from Joseph Heller's novel, Catch-22. At first it was just for fun and it was very easy to remember Yossarian, Milo, Orr, and majorx4 (Major major major major). As my network got bigger, I ran out of funny name to choose, and things started to get complicated. I started using characters from the Greek, Roman and Viking mythology, till it became a nightmare. I had to come up with a method that will help me identify nodes without remembering look-up tables in my head, so I stated looking for some kind of format that later on became very useful when I used an asset management tool.

In large network it is very common to use of some kind of database that holds records. Be it an LDAP (such as Active Directory), Yellow Pages YP/NIS, a DNS, a DHCP or a CMDB. This is why it is necessary to keep in your environment unique values for records such as computer names, usernames, asset tags and email addresses, so you can differentiate between them.

Reasons for using naming conventions:

The need for standards and uniformity
The use of logic to quickly identify objects
Granular differentiation of elements, versions, locating and security reasons
Uniqueness or records, in databases such as IDM, ITAM and others like those mention above

There are many ways you can differentiate between elements, here are some examples.

Physical differentiation – by the location of the object such as:

Subsidiary city
Building number
Floor/Level number
Room number
Factory line number

Logical differentiation – by the relation of the object such as:

Ownership - Owner user, Department, Organization Unit or Cost center
Type- Printer, Server, Computer, Switch, Filer, Desktop, Laptop, Phone or Tablet
Function – Email, DB, Web or File Servers
Permissions – Anonymous, Standard, Administrator user and so

Figure 1: Physical and Logical differentiation in Top to Bottom view

Here are some examples that might clearly the idea. First examples relate to users and employees names. I'll use my domain as an example but it can be any domain. The primary objective is to have uniformity in the convention when selecting computer names, usernames, email addresses or any other identifies, as they may affect the use in an Identity management tool.
Let's take John Doe For example, let's say that John belongs to our Chicago office, his office is in building A, he works in the marketing group, and he has a laptop, a portable projector and a mobile phone.

His employee name – Should be recorded as John Doe, not john doe, John doe, Dow john, J0hN doW! or any other combination. If you have another John Doe in your company, you may use his middle initial or any other distinguishes.

His user name - Can be set by using his Surname and a first letter from this First name such as doej or the other way around johnd or b adding another identifier, Doej01.
His email address – should be set from his employee name, such as John.Doe@partykof.com.

Notes:

You should avoid using his username as the external email address as it can giveaway his username, which makes it easier for hackers to brute force their way in.
I prefer using the dot (.) to differentiate between first name and Surname and reserve the underscore (_) to differentiate between different names, and the dash (-) for concatenated surnames. For example John_Michael.Doe-Benz@partykof.com
In cases where the user has a very long name, such as John's it might be wise to shorten the email address, JM.Doe-Benz@partykof.com

Now for John's devices, The little background we got might help us decide on suitable names for his devices.

His devices might be named as:

His Laptop - chamkt-doej-lt
His Projector- chamkt-doej-pj
His Mobile Phone - chamkt-doej-mo

I used the following schema:

CH for the Chicago branch
A for building A
MKT for marketing
DOEJ for his username
MO for mobile, PJ for projector, LT his laptop.

Some other devices around John might be:

chamkt-prt1 - his departmental printer
chamkt-plt1 - his departmental plotter
chamkt-fs1 - his departmental file server
cha-sw-core1 - his building network core switches
ch-srv-ex1 - his branch exchange server

Other areas in IT where you can use naming conventions in a similar concept are:

Storage Systems – Filers, Aggregates, Volumes, Luns, Folders
Storage Networks – Fabrics, Zones, Switches, WWNs, WWPNs
Networks – WAN and LAN elements, VLAN, VPN, DMZ, firewalls, Routers, Access Points.
Applications - Databases, Tables,

Now remember, these are only examples. You should choose your own schema for your naming conventions as it best suites your organization. There are, however, some basic rules you should comply with.

Basic Rules

Avoid using non-alphanumeric characters use only letters (A-Z) and numbers (0-9) in your computer names. Underscores and other characters may cause problems with DNS services.
Use up to 15 characters for computer names, as some services such as NetBIOS and WINS are not compatible with more.
Avoid using duplicate names, even if they are in different levels which are permitted. In some cases they can cause mix-ups, such as in the case of AD forests and OUs
Avoid schemes that will lock you in cases of mergers
Although AD supports it, a user name should not contain a space: for example, user name; as many systems do not support it.

Other Guidelines

Keep names short and meaningful as possible
When using usernames within the computer name, remember to change the computer name when you assign it to a different user.
Build your naming conventions in a top to bottom hierarchy, your prefix should start with the top element.

Some References:

Summary:

Naming records in a consistent and logical way will help distinguish between records in a glance. Naming records according to agreed conventions will make naming records much easier for all IT parties, it will streamline adoption of management application or new systems and allow a simple expansion of your organization.

-Partykof

Server management – In and out of band infrastructure – Part 1

2010-08-23T19:16:00.004+03:00

One of the numerous tasks of an administrator is to access and control IT assets across the entire organization, be it inside a local data center or on a remote office.
Located somewhere in the Middle East, I was responsible for a full production corporate data center sited in Santa Clara, CA. and support another engineering data center in Shenzhen China. This drove me to find a solution that will allow me and my group complete access in order to maintain services availability.
Usually the focus on enabling access to a server is based on the criticality of the application running on the server or the service it provides. To deliver the highest possible level of availability, you need to make sure you minimize the down time of a service - First you need to know that it is down, than you should figure out a plan for how to repair it. The time measured between the failure notifications to its repair is called, Mean Time to repair (i.e. MTTR). MTTR should be as short as possible, but it is really defined by two objectives.

Restore time objective (RTO)
Restore point objective (RPO)

Discussing these objectives is a can spread across several posts, but this post can assist with on minimizing the RTO, and deal with normal operation and not only in crisis situations.
For the sake of this discussion I will present in this post several options of connecting to a server for managing it, though in practice, only the options that will allow recovery of the service back to operation should really be implemented. To define which connections you will require, you need to come up with failure scenarios, and which connection will be utilized to overcome these failures.

The connections to a server are divided in to two major categories:

Out of Band infrastructure (OOBI) – utilizes a management channel that is isolated from the data channels.
In Band infrastructure – allowing management through the use of regular data channels, such as Ethernet network, to the managed device.

Figure 1: Server interfaces for management

Out of Band interfaces

VGA – This port refers to the display graphics output of the server, it is based on a 15-pin VGA connector to a display monitor just as you would use on a desktop. Together with a keyboard and mouse connected to the server you get a full graphical interface to the manage the local operating system (OS). Some new systems will offer DVI or HDMI interface instead of the VGA port.
Modem – A modem is an interface connected to the server, which allows remote dial-in to the server using a different network than the standard data network, it might be a standard telephone line, an ISDN connection or a GSM/UMTS/HSDPA wireless connection.
IPMI/BMC – Is a new concept based on a System-on-Chip integrated to the server’s motherboard. It allows an IP based connection to the system, and is independent from the OS status, which means it works even of the OS is down. This interface provides access to the system platform, BIOS settings, remote screen view - graphical or text mode.
Serial – Is an interface which allows a connection based on a serial protocol such as RS-232, which provides access to the system console; a legacy device such as Digital’s VT100 could provide a basic terminal interface, usually text based for performing administrative tasks to the local system.
USB – The USB interface is utilized in several ways, either by connecting the Keyboard and mouse in VGA mode, or connecting an external Modem or a remote managed UPS which can be used to power down the system.
Power – “He who controls the power control the device”. Power is the fundamental element for every electronic device. If you can power on or off the device, you have basic management over it. Such as in the case of remote routers which are not responding.
Vendor Specific – Major vendors developed dedicated interfaces to manage their appliances or devices. These implementations vary from on board solution such as Oracle’s (Sun) LOM, HP ILO or dedicated additions to the system such as IBM’s RSA card or Dell’s DRAC.

In band interfaces

Ethernet – Using the system’s network interface, the operating system could run an application that provided management capability for the system OS and its hardware platform. From the simple network management protocol (SNMP), Telnet, SSH, a full graphic Remote Desktop Connection (RDP), VNC or in some cases a vendor propriety agent, such as IBM Tivoli or BMC PATROL.
IPMI over Ethernet – In some cases, hardware manufacturers will use the Ethernet interface to provide access to the hardware platform’s System-on-Chip. It will be assigned with a different IP address in case the OS fails. This solution is very useful in dense environment and is used to save cables, switches or ever ports on the actual hardware. What it gains in saving it loses in security, as some will advise the need for a separate management network to limit access.

Connecting a single server to different kind of management interfaces can contribute a lot to the cable sprawl in your data center.

A sample for a complete solution would look something like this: (keep in mind that this is for a single server)

Figure 2: A single server management architecture

Keeping track of every server and the different ways to connect to it, is becoming a very difficult task. Just try to imagine it; you keep a table of the users, and the password, the IPMI IP addresses, the modem extensions, the power switches and the VGA monitors, for each connection. This can become a real headache.
Fortunately, there are many great solutions available today by vendors such as Avocent, ATEN, MRV and many more, that allow us to minimize this sprawl. Solutions such as multiplexed KVM switches, Serial console servers and even an IPMI portal.
In my next post - Server management – In and out of band infrastructure – part 2, I will cover such solutions.

-Partykof

Troubleshooting problems in linux, based on a sample for DD-WRT web GUI not responding

2010-07-30T12:31:00.003+03:00

In this post I am going to present a sample troubleshooting procedure for a linux box, where the web interface suddenly stop responding after few weeks of normal operation. I will present the use of basic tools embedded usually in any linux box, and an external monitoring tools based on MRTG.

I use a Linksys WRT54GS wireless router running DD-WRT v24-sp1 mega firmware. It is a small appliance that is based on Broadcom BCM4712 chip and is running a scale down linux OS. Since I installed this version I noticed that once in a while I am unable to access the web interface of the router. The simplest solution was to power cycle the router by unplugging its power plug out, but that meant getting to my router which sits in somewhere in the attic. I decided to try and figure out what was it that was causing that.

First, I configured SSH access to the router, so I would be able to remotely connect to it, and reboot it in case I needed to. I also configured SNMP monitoring for it, to collect statistics of its performance.
Once the problem reoccurred, I was able to connect to the router and run a simple top command to see what processes are running and see if it can help me figure out the problem.

Figure 1: Console view of top output

Immediately I've noticed that the router load is high, and the process that is causing that was the web server daemon, httpd which was consuming 98.2% of the cpu.
Wondering when the problem started I turned to the RRD graph and noticed that it has been going on for more than 3 weeks, at the beginning of week 28.

Figure 2: Weekly view of router CPU load

In Figure 2, you may clearly notice that the router load has dramatically changed above the load value of 1, which means that the CPU was working at 100% and was queuing processes, which in turn means performance degradation.
I tried correlating the problem to memory or traffic incident at the time the problem started. Figure 3, shows the memory utilization of the router and Figure 4 shows inbound and outbound traffic on the router WAN bridge.

Figure 3: Weekly view of router memory usage

Figure 4: Weekly view of traffic on WAN interface

Looking at the beginning of week 28 of both graphs, I found no relation to any issue at the time the problem started or that these parameters would cause this problem.

Another point that might cause an effect is the system's disk capacity, but in such a small router, the whole file system is always presented as 100% full, so this would not present an indication for a problem.

With no luck figuring out the cause of the problem, but only the symptom, I googled it, and guess what, it is a know issue. According to others in the DD-WRT community, the problem is caused from using intensive P2P services, but currently there is no resolution for it, but to use the Mini firmware version.
Since I need the Mega firmware version for VPN and VOIP, I cannot afford to downgrade my router. So the best way is to live with it. To make life easier, I wrote a small script that I can run remotely that will restart the web service, without even having to interactively login to the router.

   #! /bin/sh
   stopservice httpd
   startservice httpd

You can view a nice reference for doing this procedure in this Link

In summary, although this is only a small linux box, or a router, the basic procedure to identify a problem or its symptoms are the same, you should look at the system at normal operation and compare any irregularity to that steady state. The use of MRTG tools to collect statistics for reference is very important and useful for troubleshooting or capacity planning.

-Partykof

IBM acquires Storwize, A real-time in-line lossless data compression

2010-07-30T00:19:00.003+03:00

A new announcement is spreading across all storage magazines saying that IBM announced today that it has decided to acquire Storwize which provides real-time data compression technology.

About Storwize
Storwize, headquartered in Marlborough, MA, with an R&D office in ISRAEL, provides online storage optimization through real-time data compression. Storwize's Random Access Compression Engine™ (RACE), applied in its STN appliances, transparently (in-line) compress primary storage up to 80 percent. They promise random access and deterministic, lossless data compression with no reduction in performance.

Key Values
The Storwize solution value is based on three issues.

It is based on existing industry LZ compression algorithms, such as the one being used in standard tape backup operation, but its revolutionary idea is that it does it in real-time with no data loss.
It is very simple to deploy; it is a plug&play solution that is seamless to day to day operation, installed in less than 30 minutes. Compression can begin immediately for new data; old data is compressed seamlessly over time.
It presents immediate ROI - it allows a significant saving from day one and enables bigger operational capacity in storage and performance with current investment.

Figure 1: Typical Storwize solution

Advantages with current storage investment

An implementation of the Storwize solution will provide the following benefits.
Compress the data on existing network storage systems and save the next disk purchasing investments.
Compress data going in to the storage systems, which means it will extend the performance capacity of the current systems to a longer periods and delay the acquisition of such systems.
Immediate boosted to user experience will be as a result of this reduction of load on the storage system.
Reduce the need for users to sort, delete or compress their files and keep up with their current quota, hence freeing users from tedious tasks, and focusing on real work.
Recovery time from tapes will be reduced dramatically, as less data will be transferred from the tapes to the disks.
Power saving - Green computing - when using less disks to store compressed data, you save the power of the disks shelves that were needed for the uncompressed capacity.
Smaller footprint - Floor space savings, when using less disks shelves, you delay the need to expand the expensive data center floor space.

Risks to consider
As any new solution to be integrated in to your computer environment and being it relatively new technology on the market it presents several risks that must be address or at least be aware of.

The appliance is placed in-line between your network switch and the storage system, which means it is another failure point in the critical path of your environment. -Precaution: Make sure you deploy Storwize’s fault tolerant solution to avoid single point of failure.
Overlooked compressed configuration could result in data loss - Precaution: Set configuration control procedures and change management to avoid faults.
Introduction of a totally new system with no prior experience - Precaution: Seriously consider holding training sessions for IT personnel who will manage this environment.
Scale out lockdown when using Storwize solution with new NAS technologies. No support for global/shared name space - Precaution: Consider deploying this solution on isolated controllers at least until Storwize offer a solution for Persistent namespaces.

Conclusion
With over 18 months of experience of working with this solution, I can say, the results it presented were great. I noticed a very good compression ratio of typical data on the storage systems, while presenting performance improvements. Some configuration issues were discovered early in the deployment however they were immediately resolved by Storwize. This solution is indeed revolutionary in its concept and the results. It presents many advantages and some risks which should be addressed as advised if this solution is to be considered.

-Partykof

Configuring a server for optimal performance

2010-07-20T14:36:00.005+03:00

The preceding posts have illustrated the major building blocks that effect server configuration; I explained the importance of each one and the priority of adding it to the system.
If you missed them you can check these links:

In this final post of server configurations, I will present examples of configurations and areas where they should be applied.

Major Configurations
The configuration of a server is derived from its target application requirements. There are four major configurations

Maximum Performance
Balanced Performance
Maximum Capacity
RAS configurations

Maximum Performance

This configuration is intended to get the maximum CPU frequency, and maximum memory bandwidth. It usually uses low count of memory, as you populate only one DIMM per channel (i.e 6 DIMMS overall). The common use for such servers is for High Performance Computing ( HPC) in research organization, Oil & Gas industry and Chip Design.

Figure 1: Maximum Performance

Best configuration at the time of publishing this post:

CPU - Intel Xeon X5680 (3.33GHz), 6 cores per processor.
Memory - 6 PC3-10600 DIMMS (such as Kingston KVR1333D3D4R9SK3/24G) to allow 48GB of RAM, at 10.6GB/s bandwidth to memory.

Balanced Performance

This configuration is focused on getting a balanced configuration between the maximum CPU frequency, and maximum capacity of memory. It usually uses medium count of memory, up to 96GB per host. The common use for such servers is for virtualization and other standard enterprise applications.

Figure 2: Balanced Performance

Best configuration at the time of publishing this post:

CPU - Intel Xeon X5680 (3.33GHz), 6 cores per processor.
Memory - 2 DPC, 12 PC3-8500 DIMMS (such as Kingston KVR1066D3Q8R7SK3/24G) to allow 96GB of RAM, at 8.5GB/s bandwidth to memory.

Maximum Capacity

This configuration is focused on getting a configuration that will support the maximum capacity of memory, with a considerable compute power. It usually designed to use as much as 144GB of RAM per host ( 296GB with the upcoming 16GB modules). The common use for such servers is for very large scale database servers.

Figure 3: Maximum Capacity

Best configuration at the time of publishing this post:

CPU - Intel Xeon X5680 (3.33GHz), 6 cores per processor.
Memory - 3 DPC, 18 PC3-8500 DIMMS (such as Kingston KVR1066D3Q8R7SK3/24G) to allow 144GB of RAM, at 6.4GB/s bandwidth to memory.

RAS Configuration

RAS stands for Reliability, Availability and Serviceability. Although the ECC technology offers error correction, it does not provide any failover capability. Replacing a DIMM in case of failure requires a power down of the system. The RAS configurations offer three memory protection options:

Online spare memory mode
Mirrored memory mode
Lockstep memory mode

This configuration uses only two out the three channels.

Figure 4: RAS configuration

Online spare memory mode

In this mode, one of the channels is designed as spare. This channel is not used in normal system operation. If a working DIMM exceeds the threshold of correctable memory errors, the system switches to the standby channel and the faulty channel is taken offline.

Mirrored memory mode

In this mode, the same data is written to each channel and the read is alternated between the two channels. If a working DIMM exceeds the threshold of correctable memory errors in one of the channels, the faulty channel is taken offline and the system switches to using only one channel.

Lockstep memory mode

This mode uses two memory channels at a time, and the work as a single channel. Each read and write operations moves a data word two channel wide. To provide double 8-bit error correction within a single DRAM. This mode is the most reliable but it reduces the maximum memory capacity as the third channel is not used.
Summary
By now you should have the tools to configure your server for the optimal performance you will need for your application. You should focus on the application's memory requirements and start from that point to configure how much memory you should use and in which configuration of ranking and population.

-Partykof

Populating DIMMs considerations, Order and Ranks

2010-07-19T14:44:00.003+03:00

The Nehalem and Westmere platforms offer a wide variety of DIMM configurations. Some of the various DIMM configurations are shown below

Feature	Values
Number of DIMMs	1,2 or 3
Number of DIMMs slots per channel	2 or 3 DIMM Slots
Number of DIMMs populated per channel	1,2 or 3 DIMM per channel
DIMM Frequencies	DDR3-800, DDR3-1066, DDR3-1300

Table 1: DIMM Configurations

Populating DIMMs within a channel

When populating DIMMs in a three slots per channel configurations, a “fill-farthest” approach is used, meaning, the farthest DIMM from the processor is used first. If a Quad-rank DIMM is used, it should be populated first.

Figure 1: DIMM Population within a channel

DIMM population in an 18 DIMM slots configuration

	CPU1		CPU2
	Slot Number	Population Order	Slot Number	Population Order
Channel1	1	G	1	G
	2	D	2	D
	3	A	3	A

Channel2	4	H	4	H
	5	E	5	E
	6	B	6	B

Channel3	7	I	7	I
	8	F	8	F
	9	C	9	C

Table 2: DIMM Population in 18 DIMM Slots

Additional population requirements

All DIMMS must be DDR3 DIMMs.
The 5600 series support low voltage DDR3 memory (DDR3L) 1.35V, the 5500 supports only 1.5V, if mixed they will work at 1.5V.
Mixing Registered and Unbuffered DIMMs is not allowed.
The maximum supported speed is defined by the BIOS and not the DIMMs
Mixing different timing DIMMs will force the operation at the slowest DIMM for both processors.

RDIMM Ranks population in a three slots per channel configuration

Configuration Number	Max Speed	DIMM2	DIMM1	DIMM0
1	DDR3-1333	-	-	Single-rank
2	DDR3-1333	-	-	Dual-rank
3	DDR3-1066	-	-	Quad-rank
4	DDR3-1066	-	Single-rank	Single-rank
5	DDR3-1066	-	Single-rank	Dual-rank
6	DDR3-1066	-	Dual-rank	Single-rank
7	DDR3-1066	-	Dual-rank	Dual-rank
8	DDR3-800	-	Single-rank	Quad-rank
9	DDR3-800	-	Dual-rank	Quad-rank
10	DDR3-800	-	Quad-rank	Quad-rank
11	DDR3-800	Single-rank	Single-rank	Single-rank
12	DDR3-800	Single-rank	Single-rank	Dual-rank
13	DDR3-800	Single-rank	Dual-rank	Single-rank
14	DDR3-800	Dual-rank	Single-rank	Single-rank
15	DDR3-800	Single-rank	Dual-rank	Dual-rank
16	DDR3-800	Dual-rank	Single-rank	Dual-rank
17	DDR3-800	Dual-rank	Dual-rank	Single-rank
18	DDR3-800	Dual-rank	Dual-rank	Dual-rank

Table 3: DIMM RANKS Population in 3 slots per channel

This concludes all the basic elements we need for configuring the perfect server.

-Partykof

Intel Xeon 5600 (Westmere) family

2010-06-21T13:14:00.001+03:00

In the series of posts related to server configuration I reviewed the memory configuration for optimal performance. I figured that a short introduction to the 5600 family would be useful to better understand the considerations that will follow in my next post.

About the Xeon 5600
Part of Intel Tick-Tock cadence, The Intel Xeon 5500 (Nehalem) was shrink and replaced by Intel Xeon 5600 (Westmere) family, to be followed by Sandy Bride next year which will introduce a new microarchitecture.
The 5600 is based on the new 32nm process used in chip manufacturing and offers better performance at lower power consumption.

The 5500 and 5600 series introduced a new concept in the Xeon family, they integrate a DDR3 memory controller, that allows via 3 channels, a direct connection to a dedicated memory, up to 3 DIMMs per channel. It also includes a link controller that handles the communication with the neighbor processor in what Intel calls QuickPath interconnect (QPI). the QPI allows up to 6.4GT/s in each direction per link.

For virtualization it includes the Extended VT-x, VT-c and the VT-d technologies.
The storage interface include a 6 ports SATA2 with software raid5.

Intel introduced to these processors a new acceleration technology called, Turbo Boost Technology, which automatically allows the processor to run faster then the marked frequency in cretin conditions. The max turbo boost frequency is dependent on the number of active cores within a processor.

Figure 1: Xeon 5600 DP architecture

The Xeon 5600 platform advantages

Higher clock speeds
More cores
More cache
More memory
New instructions
Supports Low voltage DDR3 (LDDR3)

The Xeon 5600 is available in the following configurations:

Processor Model	Processor Base Frequency	Cores	L3 Cache	Power	Intel ® QPI Speed	Max Turbo Frequency	Number of Threads
X5680	3.33 GHz	6	12MB	130 W	6.4 GT / s	3.6 GHz	12
X5677	3.46 GHz	4	12MB	130 W	6.4 GT / s	3.733 GHz	8
X5670	2.93 GHz	6	12MB	95 W	6.4 GT / s	3.333 GHz	12
X5667	3.066 GHz	4	12MB	95 W	6.4 GT / s	3.466 GHz	8
X5660	2.8 GHz	6	12MB	95 W	6.4 GT / s	3.2 GHz	12
X5650	2.66 GHz	6	12MB	95 W	6.4 GT / s	3.066 GHz	12
L5640	2.26 GHz	6	12MB	60 W	5.86 GT / s	2.666 GHz	12
L5630	2.13 GHz	4	12MB	40 W	5.86 GT / s	2.4 GHz	8
L5609	1.86 GHz	4	12MB	40 W	4.8 GT / s	1.866 GHz	4
E5640	2.66 GHz	4	12MB	80 W	5.86 GT / s	2.933 GHz	8
E5630	2.53 GHz	4	12MB	80 W	5.86 GT / s	2.8 GHz	8
E5620	2.4 GHz	4	12MB	80 W	5.86 GT / s	2.666 GHz	8

Table 1: Xeon 5600 configurations

Notice the interesting low voltage processors that are available in 40 and 60 watt versions. One possible application is to use them in a passively cooled chassis (i.e. without fans).

Now that we've got the understanding of these basic elements, it is time to put things in to practice. In my next post we'll start configuring the idle server.

DIMM Ranks and configuration

2010-06-14T12:02:00.001+03:00

Server performance is highly related to its hardware configuration, In order to understand how best to configure the server a deeper understanding of its component is required. In my recent post, Introduction to DDR3 I wrote about the DDR3 technology, the different memory frequencies, 800, 1333, 1600 MHz that are adopted in recent servers CPU technology.

Another important factor to consider when configuring server memory is memory ranks, as populating a system with the wrong memory modules could result in reduction in the total capacity of the server and could create problems in performance. Some servers limit the number of memory ranks, if the number of memory ranks exceeds the specified maximum ranks set by the motherboard chipset; the server may not boot or may not operate reliably.

Memory DIMMs are configured with DRAM chips, each DRAM chip provides either 4bits (i.e x4) or 8bits ( i.e x8) of a 64bit data word. For Error Correction Code (ECC) you need 72bit, therefore 9 chips of x8 are needed to construct a 72bit data word, or 18 chips of x4.

Single-sided and double-sided DIMMs

An ECC DIMM with all nine DRAM chips on one side is called single-sided, and an ECC DIMM with nine DRAM chips on each side is called double-sided ( see Figure 1). A single-sided x8 ECC DIMM and a double-sided x4 ECC DIMM each create a single block of 72bits (64bits plus 8 ECC bits).

Single-rank, dual-rank, and quad-rank DIMMs

DIMMs are also classified to ranks. The definition of a rank is an area or block of 64-bits (72bits for ECC memory). A single-rank ECC DIMM uses all of its DRAM chips to create a single block of 72bits, and all the chips are activated by one chip-select (CS) signal from the memory controller. A dual-rank will require two chip-select signals as it produces two blocks from two sets of chips on the DIMM. The same logic applies to Quad-rank, where you need four CS signals.

Figure 1: 72bit SDRAM DIMMs and corresponding DIMM rank

The first advantage for higher rank DIMM is the greater capacity they can offer per the available DIMM slots on the server’s motherboard. The second advantage is related to latency, where there is a higher probability for the memory controller to relocate pending memory pages.
The number of ranks per channel also effects the performance, with an odd number of ranks per channel there is performance disadvantage of realistically 2-3%. Since there 3 channels per CPU, the use dual-rank DIMMS will always result in an even number of ranks, which is another good reason why to use it.

Introduction to DDR3

2010-06-12T16:39:00.000+03:00

Recent CPU technology has adopted the use of high speed memory module, which makes server configuration a bit tricky. I often had to figure out what kind of memory modules to use on my servers, be it a Database Server, an High Performance Computing (HPC) node or a Virtualization platform.

I hope the next series of posts will help shed some light on this matter and assist building the optimized platform for your application.

First we must understand the basics of memory technology that is currently used.

JEDEC - Joint Electronic Device Engineering Council, is the group that set memory industry standards ,aspects such as features, functionality, AC and DC parameters, data interfaces and more.

The DDR3 SDRAM is the latest one used for servers. It is a high-speed dynamic random-access memory internally configured as an eight-bank DRAM. The DDR3 SDRAM uses a 8n prefetch architecture to achieve high-speed operation. The 8n prefetch architecture is combined with an interface designed to transfer two data words per clock cycle at the I/O pins.
Theoretically, these modules could transfer data at the effective clockrate of 800-1600MHz (for a single clock bandwidth of 400-800MHz), producing a throughput of 12800 MB/s.

Chart 1: SDRAM technologies throughput

Compatibility

DDR3 DIMMS have 240 pins, the same number as DDR2; however, since the supply voltage is different DDR3 uses 1.5V where DDR2 uses 1.8V they are incompatible. To identify between them, the DIMMS are also physically incompatible. The key notch location is different. so DO NOT try forcibly to install them.

DDR3 Advantages

Higher Performance – The most important benefit is the ability to transfer 8bits of data in 1 clock cycle, which is twice than DDR2. Higher throughput equals higher performance.
Lower Power – DDR3 memory operate at 1.5V supply, which is 17% less than what DDR2 uses. This low power results in improving the thermal design using 30% less power.
Larger Density – Since the DDR3 allows higher chip capacity (1GB<) it allows a maximum memory modules of 16GB.
Data Integrity – An integrated thermal sensor refreshes the data in the device and ensures data integrity and data drainage during transfers
Higher Speed – Twice the speed of DDR2, it has the ability to transfer I/O data eight times the speed of the memory cell it contains.

DDR3 Standard Modules

Module Name	Standard Name	Memory Clock	I/O Bus Clock	Data Rate	Peak Transfer Rate
PC3-6400	DDR3-800	100 MHz	400 MHz	800 MT/s	6400 MB/s
PC3-8500	DDR3-1066	133 MHz	533 MHz	1066 MT/s	8533 MB/s
PC3-10600	DDR3-1333	166 MHz	667 MHz	1333 MT/s	10667 MB/s
PC3-12800	DDR3-1600	200 MHz	800 MHz	1600 MT/s	12800 MB/s

Table 1: DDR3 standard memory modules

Note that Standard’s name correlates to the clockrate, not the Memory Clock or the Bus Clock, i.e DDR3-1600 offers the clockrate of 1600MHz.

Since memory configuration and capacity is effecting server performance, it is very important to understand which modules to use in which configuration. For example, populating all memory banks with the fastest modules (DDR3-1600) will cause the system to work as if DDR3-800 where used. in the next posts I’ll try to explain why.

Google Search made easy

2010-06-11T01:23:00.001+03:00

Since it has become the most useful tool when using the internet, and it even got a catchy name for it (i.e. "Google it!"), I thought it might even more useful if I summarize some nice tips to tweak the search for the most accurate results.

Now, you may use the formatted Google Advanced Search or you can just learn the simple key words that will help you narrow your search.

First for the basics:

1. Every word you enter counts
2. [ Yin and Yang ] is one query, while [ Yin ] and [ Yang ] are two separate queries.
3. Punctuation is ignored, including @#$%^&*()=+[]\ and other special characters.
4. Use the words that are most likely to appear on the page.
5. The more unique the word is the more likely you are to get relevant results.

The cool stuff:

Phrase search ("") - Looks for exact words in that exact order without any change.
Search within a specific website (site:) - Limit your search to a particular domain name.
Terms you want to exclude (-) - Use the minus sign to omit searches that include words you want to exclude.
Wild card (*) - The search treats the star as a placeholder for any unknown term(s) and then find the best matches.
Exactly as is (+) -Since Google employs synonyms automatically, this key tells it to ignore it.
The OR operator (|) - Since usually every word counts, this key specifically allow either one of several words.
File extension (filetype:) - Display results that include only specified file types.
Search title (intitle:) - Display results that include the specified title in a document.

Now let's put this in to action

Example 1 - The search entry:
"burning down the house" "talking heads"|tom jones" site:youtube.com Try it Now
Will search for "Burning down the house" by Talking Heads or by Tom Jones only on youtube.com

Example 2 - The search entry:
intitle:vitae site:uk programmer -submit -apply ext:doc | ext:pdf Try it Now
Will search for the word "vitae" on UK domains, include the word programmer exclude the words submit apply and only in files that have the extensions .doc and .pdf

Example 3 - The search entry:
funny * +screams mirror site:youtube.com Try it Now
Will search for the word funny and then some word, the exact phrase screams and the word mirror on youtube (BTW, that's my girl that is screaming there)

Well, these are the basics, from here on out you can use any combination you choose to narrow your search to get the best results.
To find out more about the advance search options and the exceptions that it offers use Google help pages.

Free Personal Cloud Storage

2010-05-21T19:30:00.001+03:00

Personal Cloud Storage solution enables users to store, share, collaborate and access files – anytime, anywhere and from any device they choose. A desktop, a laptop or a mobile phone.
The Personal Cloud storage solution features secure online file storage, file sharing and in many cases some advanced collaboration, content tagging and true anytime, anywhere access from a variety of access clients. Some offer only basic web access, some offer other protocols such as SSL, ftp, Web DAV, while other include integration with the OS file manager.

What I was looking for was a solution that is basically free, or offers a free quota to start with, and can expand to bigger quota and SLA solution, which is usually charged. The services I chose to use were the ones close to the services I was already using.

Google Documents - using my Google account
Windows Live Skydrive - using my MSN account
Ubuntu One - embedded with my Ubuntu laptop
Dropbox - just because it syncs on all platforms
Adrive - just cause they were the first who offered 50GB for free

Service	Free Quota	Access	Search	Upgrades	Features
Google Docs	1 GB	Web	Yes	20GB - $5/y 80GB - $20/y	Read More
Skydrive	25 GB	Web	No		Read More
Ubuntu One	2 GB	Web Ubuntu Nautilus	No	50GB - $9.99/m	Read More
Dropbox	2 GB	Web Windows Explorer Ubuntu nautilus	Yes	50GB - $10/m	Read More
Adrive	50 GB	Web Web DAV FTP Native Client	Yes	50GB - $6.95/m	Read More

I must confess that I am using all of these services by now. but it makes it very difficult to keep track of what I put where. So I decided to use the services according to the types of content I store on them.

My favorite service is Google Docs as it allows indexing of most of the content you place there, which is very easy to search and tag. so I keep most of my Documents, Presentations, and PDF files there. For such working documents I don't need more than the 1GB offered for free. maybe one day when Google Gdrive comes out it will be more attractive.

Image 1: Google Documents

The Adrive is my archiving platform, where I keep my photos and videos which don't really need indexing. Documents and other files that I finished working on I archive there too. and what can I say the 50GB quota is a bliss.

Image 2: Adrive

For that same purpose you may use Skydrive if 25GB is enough for you. it is more convenient as you probably already own a Live account and the offer Sync to your desktop with Windows Live Sync.

Image 3: Windows Live Skydrive

Both Dropbox and Ubuntu one, are integrated with my file manager so it is very easy to use them, and you can search them using your operating systems search capabilities, which is nice BUT, you cannot search them from the web, which is something I really like as I am not always using my devices.

Image 4: Ubuntu One

Another great feature of both these services is that the sync the local folder with the folders in the cloud storage.

Image 5: Dropbox

Very important Note: Since what I reviewed here are free of charge services, you cannot really expect any service level agreement (SLA) from the provider. therefor, I would highly recommend not to store any private material, such as personal records, credit or any personal data that might leak, furthermore, I would recommend that you keep an On-premise copy (on a DVD or Local Drive) of the important stuff you keep in the cloud, just in case someone decides to retire the service he is currently offering, such as Yahoo! did with their Briefcase service.

To summaries, I cannot tell you which one is best, only you can decide for your own. I hope I gave you some insight about the services and what they offer, and that might help you select your favorite.

-N.J.

Firefox extensions that make my browsing much easier

2010-05-11T17:42:00.003+03:00

Firefox has establish itself as a good replacement for Internet Explorer(IE), it’s a fact. But what sets it apart from all other browsers is the ability to add extensions. You have a very wide selection of them, but I found that there are some that make my life much easier, and I consider them as a killer-app extension, which made me forsake IE for good. Here are my favorite extensions.

1. FEBE

FEBE (Firefox Environment Backup Extension) allows you to quickly and easily backup your Firefox extensions. In fact, it goes beyond just backing up -- It will actually rebuild your extensions individually into installable .xpi files. Now you can easily synchronize your office and home browsers.

2. IE Tab 2

Updated and enhanced version of the classic IE Tab that features embedding Internet Explorer in tabs of Mozilla/Firefox (Note that it works only on Windows OS). Most useful if you use SharePoint or other Microsoft sites, and retires the use of IE altogether.

3. Adblock Plus

Annoyed by adverts? Troubled by tracking? Bothered by banners? Install Adblock Plus now to regain control of the internet and change the way that you view the web. A short video overview is available at http://www.youtube.com/watch?v=oNvb2SjVjjI

4. Gmail Manager

Allows you to receive new mail notifications along with viewing account details including unread messages, saved drafts, spam messages, labels with new mail, space used, and new mail snippets..

5. Speed Dial

With Speed Dial, you can easily access your most used websites. To show the Speed Dial tab, use the Speed Dial button (which can be added to the toolbar)

6. GBookmarks

This extension allows you to access Google Bookmarks. It creates a menu in Firefox using which you can add, edit and remove bookmarks. So, you can access your bookmarks from any computer. You don't have to mail a link if you want to save or access bookmarks across computers, just use this extension...

7. Greasemonkey

Allows you to customize the way a webpage displays using small bits of JavaScript. Hundreds of scripts, for a wide variety of popular sites, are already available at http://userscripts.org. you can use Greasefire Add-on too and when you visit a web page that has compatible user scripts on Userscripts.org, this extension will highlight the Greasemonkey icon in the status bar. Right click the Greasemonkey icon and choose the "X scripts available" item to see and install the scripts available for the current page. (requires Greasemonkey)

8. Better Gmail

Add useful extra features to Gmail, like hierarchical labels, an unread message icon on your browser tab, file attachment icons, and more.

9. Better YouTube

A compilation of some of the best Greasemonkey user scripts for YouTube in one interface

10. Securelogin

Secure Login is a login extension for Mozilla Firefox integrated password manager.

Its main feature is similar to Opera's (the browser) Wand login.

Partykof... what the hack does that mean?

2010-05-10T23:43:00.014+03:00

Partykof is a slang word distorted from the phrase "Power take-off" which refers to a switch located on the front console of a Tractor, This word is commonly used among the Kibbutz members (the Kibbutznikim) in Israel.

A power take-off (PTO) is a splined driveshaft, usually on a tractor or truck, that can be used to provide power to an attachment or separate machine. It is designed to be easily connected and disconnected. The power take-off allows implements to draw energy from the tractor's engine.

Image1: The PTO on the back of the Tractor - Find out more on Wikipedia

I decided to use this analogy as most of the information I gather, comes from the Internet, and harnessing it's power for the benefit of IT is what I do.