Welcomes Everything

noreply@blogger.com (Murthy) — Sat, 30 Jun 2012 13:45:00 -0700

http://redleg.nl/klang.html?nck=nruvji

Pictures taken at San Diego Zoo.

noreply@blogger.com (Murthy) — Thu, 3 Sep 2009 16:21:00 -0700

Meer Cat basking in the evening sun.

Erasing VLAN.DAT file.

noreply@blogger.com (Murthy) — Thu, 3 Sep 2009 09:40:00 -0700

Today I tried deleting VLAN.DAT file from a Catalyst 4948 series switch, but I was getting the following error.

%Error deleting cat4000_flash:vlan.dat (Permission denied)

I could not find the actual cause of it but I found a work around. Instead of delete command I used erase command. One thing to remember is erase command deletes all files ffrom the cat4000_flash.

The command syntax is “ erase cat4000_flash:”. Type yes to confirm that you wanted to erase the cat4000_flash;

Hope this will help you.

Thank you.

Mapping Cisco old commands to new commands.

noreply@blogger.com (Murthy) — Tue, 1 Sep 2009 11:21:00 -0700

Old Command	New Command
configure network	copy ftp:[[[//[username[:password]@]location]/directory] /filename] system:running-config
configure overwrite-network	copy ftp:[[[//[username[:password]@]location]/directory] /filename] nvram:startup-config
copy rcp running-config	copy rcp:[[[//[username@]location]/directory]/filename] system:running-config
copy running-config rcp	copy system:running-config rcp:[[[//[username@]location]/directory]/filename]
copy running-config startup-config	copy system:running-config nvram:startup-config
copy running-config tftp	copy system:running-config tftp:[[[//location]/directory]/filename]
copy tftp running-config	copy tftp:[[[//location]/directory]/filename] system:running-config
copy tftp startup-config	copy tftp:[[[//location]/directory]/filename] nvram:startup-config
erase startup-config	erase nvram:
show configuration	more nvram:startup-config
show file	more
show running-config	more system:running-config
write erase	erase nvram:
write memory	copy system:running-config nvram:startup-config
write network	copy system:running-config ftp:[[[//[username [:password]@]location]/directory]/filename]
write terminal	more system:running-config

Interesting facts about LED TV.

noreply@blogger.com (Murthy) — Wed, 19 Aug 2009 10:52:00 -0700

I found the below interesting facts from http://www.vizio.com/about.aspx?cid=3519&id=2892

----------------

When a product has become commoditized and its price is regularly dropping and its profit margins are getting ever-thinner, how can a company boost its sales and raise its prices?

One way is by changing the product’s name.

That’s what Samsung has done with its new line of LCD TVs using LEDs to illuminate the screen. In its print advertising and on its Web site, Samsung calls their new range simply “LED TVs.”

They are not LED TVs. Calling them such makes as much sense as calling its existing line of LCD televisions Cold Cathode Fluorescent Lamp TVs, or CCFL TVs, after the lighting technology that they use.

Whatever its validity, Samsung’s decision to drop “LCD” was a smart marketing move. After all, “LED” is the acronym du jour, a technology that’s all the rage as a new, perhaps revolutionary lighting source. It’s as emotive a term as “HDTV” and “digital” were in their heydays.

But it’s also confusing consumers. An industry colleague told me that in a recent trip to a big-box retailer, he overheard several friends asking what type of TV they were watching. One said it wasn’t LCD or plasma, it was an LED set.

More accurately, it was an expensive LCD set. LED-backlit LCD TVs can cost as much as twice their standard LCD or plasma counterparts. Is the extra money worth it, even if you can afford it?

Here are the answers to some questions you may have about LCD TVs using LED backlighting.

What’s wrong with existing LCD TVs?

Up until now, LCDs used fluorescent tubes to light the screen. As a result, LCDs have trouble creating deep blacks. That’s because fluorescent tubes are always on, and some light leaks through to the front of the display even when a part of the image is supposed to be black. A lack of deep blacks reduces the perceived sharpness of the set’s image.

Also, fluorescents lack a wide range of colors; hence, color saturation is limited.

What’s an LED TV?

It’s an LCD TV that uses LEDs to illuminate the display. There are two ways to do this: either by placing LEDs across the entire back of the display, or by placing LEDs just around the perimeter, which is called an “edge lit” display. Both techniques use less power than plasma TVs and LCD TVs lit with fluorescent tubes.

Which technique is better?

They both have their pros and cons. LCD TVs using edge-lit LCDs can be ultra-thin, because the LED sources are on the side. Edge-lit LED-lit LCDs are also less expensive than LCD TVs using LED backlit technology.

On the other hand, LCD TVs that use LEDs across the rear of the display can create dramatically deeper blacks, through a technique called “local dimming.” When a scene calls for a dark image, the LEDs in that area can be shut off completely, so no light leaks through what should look black.

So if I Want an LED-lit LCD, I should buy one using back-lit technology?

It’s not so simple. An LED backlit TV may contain only about 1,000 LEDs. And those LEDs can only be dimmed in large groups, because it is too expensive to control each LED individually. So when you shut off or dim a group of LEDs you may also be darkening part of an adjoining scene on the TV that really should be bright. If you cut back on the dimming, then the blacks will be less dark than blacks in another part of the image that are not surrounded by lighter images.

Theoretically, you could increase the number of LEDs so that each lit just one pixel on the 2 million pixel LCD screen. But then you could just throw away the LCD screen because you would have actually created an LED television—just like the Walgreen’s LED sign in Times Square.

Okay, but still, LCD TVs with LEDs Have Great Contrast

Sometimes they do. It depends on what you’re watching. As a Samsung engineer said to me last week, “the most dramatic effect of LED-lit TVs happens when the entire scene goes to black”—not necessarily when you’re watching a scene with a mixture of light and dark images.

Do LED-lit LCD TVs Produce Better Pictures than Plasma TVs?

Interestingly, I’ve heard no one in the industry claim that they do. At best, they say that with LED-lit LCD TVs, plasma no longer has an edge when it comes to creating deep blacks and saturated colors. But plasma still has a dramatic edge when it comes to price.

How Much More Do LED-Lit LCD TVs Actually Cost?

Right now, a lot. But that should change as more companies enter the market. The list price for Samsung’s 46-inch high-end LED-lit LCD TV, model UN46B8000, is $3,200. But its larger 50-inch plasma high-end model, the PN50B860, is $800 cheaper.

Later this year, LG will launch two new series of LED LCD TVs, in 42, 47, and 55-inch screen sizes; all sets will use backlit LED technology. Prices have not been announced.

Not surprisingly, Vizio has just broken the LED price barrier. On Monday, the company announced that beginning this September it would ship the VF551XVT, a 55-inch LCD model using LED backlighting. The price: $2,200, or $1,000 less than Samsung’s smaller 46-inch LED-lit television. It looks like Samsung’s strategy to make its LED-based LCD TVs a premium product may have a short life.

Port speed and duplex auto negotiation.

noreply@blogger.com (Murthy) — Mon, 17 Aug 2009 14:25:00 -0700

Note: This section is only applicable for 10/100/1000 Mbps (1000BASE-T) NICs, and not 1000BASE-X NICs.

Table 1—Autonegotiation Valid Configuration

Configuration NIC (Speed/Duplex)	Configuration Switch (Speed/Duplex)	Resulting NIC Speed/Duplex	Resulting Catalyst Speed/Duplex	Comments
AUTO	AUTO	1000 Mbps, Full-duplex	1000 Mbps, Full-duplex	Assuming maximum capability of Catalyst switch, and NIC is 1000 Mbps, full-duplex.
1000 Mbps, Full-duplex	AUTO	1000 Mbps, Full-duplex	1000 Mbps, Full-duplex	Link is established, but the switch does not see any autonegotiation information from NIC. Since Catalyst switches support only full-duplex operation with 1000 Mbps, they default to full-duplex, and this happens only when operating at 1000 Mbps.
AUTO	1000 Mbps, Full-duplex	1000 Mbps, Full-duplex	1000 Mbps, Full-duplex	Assuming maximum capability of NIC is 1000 Mbps, full-duplex.
1000 Mbps, Full-duplex	1000 Mbps, Full-duplex	1000 Mbps, Full-duplex	1000 Mbps, Full-duplex	Correct Manual Configuration
100 Mbps, Full-duplex	1000 Mbps, Full-duplex	No Link	No Link	Neither side establishes link, due to speed mismatch
100 Mbps, Full-duplex	AUTO	100 Mbps, Full-duplex	100 Mbps, Half-duplex	Duplex Mismatch ¹
AUTO	100 Mbps, Full-duplex	100 Mbps, Half-duplex	100 Mbps, Full-duplex	Duplex Mismatch ¹
100 Mbps, Full-duplex	100 Mbps, Full-duplex	100 Mbps, Full-duplex	100 Mbps, Full-duplex	Correct Manual Configuration²
100 Mbps, Half-duplex	AUTO	100 Mbps, Half-duplex	100 Mbps, Half-duplex	Link is established, but switch does not see any autonegotiation information from NIC and defaults to half-duplex when operating at 10/100 Mbps.
10 Mbps, Half-duplex	AUTO	10 Mbps, Half-duplex	10 Mbps, Half-duplex	Link is established, but switch does not see Fast Link Pulse (FLP) and defaults to 10 Mbps half-duplex.
10 Mbps, Half-duplex	100 Mbps, Half-duplex	No Link	No Link	Neither side establishes link, due to speed mismatch.
AUTO	100 Mbps, Half-duplex	100 Mbps, Half-duplex	100 Mbps, Half-duplex	Link is established, but NIC does not see any autonegotiation information and defaults to 100 Mbps, half-duplex.
AUTO	10 Mbps, Half-duplex	10 Mbps, Half-duplex	10 Mbps, Half-duplex	Link is established, but NIC does not see FLP and defaults to 10 Mbps, half-duplex.

DVDs for cheap price.

noreply@blogger.com (Murthy) — Mon, 17 Aug 2009 12:24:00 -0700

Moserbaer is trying beat piracy by reducing the prices. It is definitely great idea.

You can buy DVDs online from the following link.

http://moserbaer.com/moserbaer_entertainment.asp

They have various genres.

1. Classic

2. Comedy

3. Adult(not true.)

4. etc.

Enjoy.

Best site for Network Cheatsheets.

noreply@blogger.com (Murthy) — Fri, 14 Aug 2009 13:05:00 -0700

I found this website has the best network cheatsheets.

http://mion.faireal.net/BES/

Monetizing the blog.

noreply@blogger.com (Murthy) — Fri, 14 Aug 2009 10:51:00 -0700

I have been working on my blog to monetize and make minimum of 10 US$ per day. I have been modifying layout of my blog to attract more traffic but no luck. It is well above my head how Google payout for the adds. I understood adsense this way

1. More number visits pays more money

2. All clicks on ads pays money

But the results did not match. I do not know what formula does google follow to pay. I tried understanding the formula from adsense website but it was kind complex.

I am not criticizing Google, but trying to understand it.

I feel the highest paying ads will be displayed on the blogs with the following key words. It is purely my opinion and there is no scientific explanation for it.

1.mortgage

2.makeup

3.porn

4.sex

5.medication

6.autos

etc.

Hope someone understand Google's payout policy and explain's it to all.

Thank you.

Murthy

Reebok 40% discount coupon.

noreply@blogger.com (Murthy) — Tue, 11 Aug 2009 09:05:00 -0700

Please check this 40% discount coupon from Reebok. It expires by August 16th 2009.

http://www.reebokoutletmail2.com/Q15343/Q15343.asp?r=5433_72960&i=Q15343002&e=suryanarayanamurthy@gmail.com&b=0081522933

Auctions for free stuff.

noreply@blogger.com (Murthy) — Wed, 5 Aug 2009 09:46:00 -0700

Wow! Now you can auction for free stuff at this site. Interesting.

http://www.listia.com/signup/1240

Junos like open source routing software.

noreply@blogger.com (Murthy) — Mon, 3 Aug 2009 11:15:00 -0700

I simulate networks with Cisco and Juniper routers on my PC to study and understand very well about routing protocols. With GNS3 my life became simple in emulating Cisco routers. Running Juniper routers on Olive is kind tedious but one of my friends was gracious enough to prepare an Olive VM for me. But I wanted to run more routers with less trouble and I found that the following company offers a Junos like OS for free(offcourse without support). They do have some paid services which I do not need to care at this point. Please click on the following link to more about their product and download.

http://www.vyatta.com/

Emulating Cisco ASA firewall.

noreply@blogger.com (Murthy) — Mon, 3 Aug 2009 11:13:00 -0700

I have been trying to emulate Cisco ASA firewall various ways on my PCs. I used GNS3 and Qemu until I found this website recently. It is very easy now to emulate an ASA in VMWare using this ISO. Please try.

http://asa_project.gromnet.net

Container gardening.

noreply@blogger.com (Murthy) — Sat, 1 Aug 2009 09:23:00 -0700

I live in a single bed room rental apartment which has a small patio. Luckily I get lot of light in the patio. I got so crazy about container gardening. I did not setup a goal to grow vegetables to reduce my costs, but I wanted to entertain myself by taking care of the plants. I looked around internet for various ideas. I found the following link is very useful.

http://aggie-horticulture.tamu.edu/extension/container/container.html

Gardening is kind of mental relaxation for me. I feel realxed when I see plants growing. I feel relaxed when I take care of plants. I feel that I am achieving something when the plants grow and start giving flowers etc.

I will keep posting progress of my container garden.

Cheers.
Murthy

Time stamping the show commands.

noreply@blogger.com (Murthy) — Wed, 25 Feb 2009 11:16:00 -0800

If you want to time stamp the show commands along with current CPU utilization for a particular session, issue the following command.

terminal exec prompt timestamp

enable

Sample Output:

cs1#show run

Load for five secs: 0%/0%; one minute: 1%; five minutes: 1%

Time source is NTP, *11:00:00.713 Pacific Wed Feb 25 2009

Building configuration...

Current configuration : 30463 bytes

Cisco Hidden command for fabric utilizations.

noreply@blogger.com (Murthy) — Fri, 30 Jan 2009 10:37:00 -0800

show plat hard cap fabric

The output of the above command gives bus utlization etc. It is a very nice command

Identifying the backplane utilization on Catalyst 6500.

noreply@blogger.com (Murthy) — Wed, 28 Jan 2009 09:42:00 -0800

You always wanted to know the peak backplane utilization of Catalyst 6500 series switch and when it occurred. You can find those details by typing this command.

cs1 #show catalyst6000 traffic-meter

traffic meter = 0% Never cleared

peak = 51% reached at 17:07:23 Pacific Thu Dec 20 2007

You can also setup SNMP monitoring and Syslog to alert you if the utilization crosses pre-defined values. You can find more details on this at,

http://www.cisco.com/en/US/tech/tk648/tk362/technologies_tech_note09186a0080094a96.shtml

Hope this command is useful to you. If yes, please leave feedback.

Thank you.

Murthy

noreply@blogger.com (Murthy) — Thu, 11 Dec 2008 11:08:00 -0800

Fiber Optic Circulator Applications

Add-Drop Multiplexing
Fiber Sensors
Bi-directional Pumping
Bi-directional Signal Transmission Systems
Coupling In-line Chromatic Dispersion Compensation Devices

Fiber optic circulators are non-reciprocating, one directional, three-port devices that are used in a wide range of optical setups and for numerous applications. An optical circulator is analogous to an electronic circulator and both perform similar functions. An optical circulator is a three-port device that allows light to travel in only one direction. A signal entered to Port 1 will exit Port 2, while a signal entering Port 2 will exit Port 3 all with minimal loss. Light entering port 2 experiences a large amount of loss at port 1, and light entering port 3 experiences a large amount of loss at ports 2 and 1.

Optical circulators are non-reciprocal optics. This means that any change in the properties of the light caused by passing through the device are not reversed by traveling in the opposite direction. Another example of non-reciprocal optics are Faraday rotators which are sometimes used in isolators.

Because of its high isolation and low insertion loss, optical circulators are widely used in advanced communication systems as add-drop multiplexors, bi-directional pumping, and chromatic dispersion compensation devices.

The example to the right depicts the use of a circulator to drop an optical channel from a DWDM system using a fiber bragg grating. The input DWDM channels are coupled into Port 1 of the device with a FBG device connected to Port 2. The single wavelength reflected off the FBG then reenters the circulator in port 2 and is routed accordingly to Port 3. The remaining signals pass through the FBG and exit on the top fiber.

Circlulators can also be used to send optical signal in two directions down a single fiber. A circulator is located at both ends of the fiber. Each circulator functions to add a signal in one direction while removing the signal in the other. See the example below.

Juniper Training.

noreply@blogger.com (Murthy) — Mon, 24 Nov 2008 09:24:00 -0800

During my training at Juniper last week I found these important document resources. I felt that these will be useful for all and sending across. The training basically covered all the topics for JNCIA-M. The training was great. Now I feel very comfortable with Junos configurations. Obviously I should keep using what I learnt there :)

JNCIA-M Study Guide:
You can download all the study guides from Juniper for free. Herewith I am attaching the link for JNCIA study Guide. I am motivated to take this exam.
http://www.juniper.net/training/certification/JNCIA_studyguide.pdf

Juniper Technical documents:
This link has all Juniper technical documentation. It will be worth to book mark.
http://www.juniper.net/techpubs/

Junos to IOS command reference:
I thought I need to make a list of equivalent commands in Junos to IOS, but they have it already on their website. You can download that from the following link.
https://www.juniper.net/customers/csc/documentation/techdocs/downloads/pdf/350023.pdf

Juniper router simulators:
Not but least. The following links explain how to simulate Juniper router on your PC. The simulator will help you in practicing the commands and other features.
http://www.smogey.net/tech/Juniper/Olive/index.htm#credit
http://brokenpipes.blogspot.com/2008/01/olive-is-alive.html

Please let me know if you have any questions.

Thank you.

Junos Documentation.

noreply@blogger.com (Murthy) — Thu, 20 Nov 2008 15:51:00 -0800

JNCIA Study Guide can be downloaded from:

http://www.juniper.net/training/certification/JNCIA_studyguide.pdf

Juniper Technical Documentation can be found at:

http://www.juniper.net/techpubs/

Mapping of basic Junos commands to IOS commands

https://www.juniper.net/customers/csc/documentation/techdocs/downloads/pdf/350023.pdf

IP Fast Switching, Process Switch and CEF Switching.

noreply@blogger.com (Murthy) — Mon, 10 Nov 2008 11:11:00 -0800

I found nice information on Fast Switching, Process Switch and CEF Switching in the following link.

http://ciscogeek.wordpress.com/2008/10/14/ip-switching-fast-switching-process-switching-cef-switching/

Cisco Express Forwarding vs Fast Switching:

noreply@blogger.com (Murthy) — Wed, 5 Nov 2008 12:05:00 -0800

Cisco Express Forwarding vs Fast Switching:

Enabling CEF may be a method to alleviate the increased traffic load . CEF is supported in IOS releases 11.1( )CC, 12.0, and later on the Cisco 7200/7500/GSR platforms. Support for CEF on other platforms may be in IOS release 12.0 or later. You can investigate further with the Software Advisor tool on CCO.

It may not be possible to enable CEF on all routers for one of the following reasons:

--Insufficient memory

--Unsupported platform architectures

--Unsupported interface encapsulations

Fast Switching Behavior and Implications:

The following are implications of using fast switching:

--Traffic driven cache, or the cache is empty until the router switches packets and populates the cache.

--First packet is process switched (since cache is initially empty).

--Cache built at a granularity of the most specific Routing Information Base (RIB) entry part of a major net (if RIB has /24s for major net 131.108.0.0, the cache is built with /24s for this major network).

--/32 caching for load balancing - per destination load-balancing only (when load balancing, cache is built with /32s for that major net).

Note: These last two issues can potentially cause a huge cache that would consume all memory.

--With default route, caching is done at major network boundaries.

The Cache Ager runs every minute and checks 1/20th (5 percent) of the cache for unused entries under normal memory conditions, and 1/4th (25 percent) of the cache in a low memory condition (200k).
The command to change the above values is: ip cache-ager-interval X Y Z, where:

X is <0-2147483> number of seconds between ager runs, default = 60 seconds.

Y is <2-50> 1/(Y+1) of cache to age per run (low memory), default = 4.

Z is <3-100> 1/(Z+1) of cache to age per run (normal), default = 20.

CEF Advantages:

--The Forwarding Information Base (FIB) table is built based on the routing table, therefore forwarding information exists before the first packet is forwarded. The FIB also contains /32 entries for directly connected LAN hosts.

--The Adjacency (ADJ) table contains the Layer 2 rewrite information for next-hops and directly connected hosts (an ARP entry creates a CEF adjacency).

--There is no cache ager concept with CEF to spike CPU utilization. A FIB entry is deleted if a routing table entry is deleted.

--There is a more efficient lookup with CEF (maximum of 4 lookups).

Caution: Again, a default route pointing to a broadcast or multipoint interface means that the router will ARP for every new destination, potentially creating a huge adjacency table until the router runs out of memory. If CEF fails to allocate memory CEF/DECF will disable itself and will have to be manually re-enabled.

AutoSecure feature in Cisco IOS.

noreply@blogger.com (Murthy) — Thu, 9 Oct 2008 16:16:00 -0700

AutoSecure

By using a single command-line interface (CLI), the AutoSecure feature allows a user to perform the following functions:

•Disable common IP services that can be exploited for network attacks

•Enable IP services and features that can aid in the defense of a network when under attack.

More details can be found from:

http://www.cisco.com/en/US/docs/ios/12_3/feature/guide/ftatosec.html#wp1027129

Understanding Access Control List Logging

noreply@blogger.com (Murthy) — Thu, 9 Oct 2008 12:41:00 -0700

Please find the following extracts from Cisco's website which help in reducing CPU by ACL logging.

---------------------------------

There are two primary factors that contribute to the CPU load increase from ACL logging: process switching of packets that match log-enabled access control entries (ACEs) and the generation and transmission of log messages.

The log and log-input Access Control Entry OptionsL:

The log and log-input options apply to an individual ACE and cause packets that match the ACE to be logged. The log-input option enables logging of the ingress interface and source MAC address in addition to the packet's source and destination IP addresses and ports.

The first packet logged via the log or log-input options will generate a syslog message. There are two scenarios in which subsequent log messages will not be sent immediately. If the log-enabled ACE matches another packet with identical characteristics to the packet that generated a log message, the number of packets matched is incremented and then reported at five-minute intervals. Similarly, if any log-enabled ACE in any ACL on any interface matches a packet within one second of the initial log message, the match or matches are counted for five minutes and then reported. These periodic updates will contain the number of packets matched since the previous message.

Configuring a Log Update Threshold:

The ip access-list log-update threshold threshold-in-msgs and ipv6 access-list log-update threshold threshold-in-msgs commands can be used to configure how often syslog messages are generated and sent after the initial packet match. These commands use a threshold described as a number of packets, not as a time interval. This is in contrast to the periodic updates, which are sent every five minutes. A user configurable, time-based threshold does not presently exist.

Limiting ACL Logging–Induced Process Switching:

The ip access-list logging interval interval-in-ms command was released in IOS version 11.3. This command limits the effects of ACL logging–induced process switching by providing a rate limit for process-switched packets. The interval configured in the command allows only one packet per interval to be process switched no matter how many log-enabled ACEs exist. The interval applies globally, and the process switching limit affects all log-enabled ACEs in all ACLs on all interfaces. Packets that are not process switched will not be examined and will not be accounted for in logging. This functionality requires Cisco Express Forwarding to be enabled using the ip cef global configuration command.

The ip access-list logging interval interval-in-ms command does not apply to logging-enabled IPv6 ACLs and there is no IPv6 equivalent. As a result, all packets matching log-enabled ACEs in IPv6 ACLs are process switched.

Administrators can determine the number of packets being process switched using the show interface switching EXEC command. Although log messages may not be comprehensive after enabling the ip access-list logging interval command, the counter values displayed using the show access-lists and show ip access-lists commands are updated properly regardless of the presence or configuration of the ip access-list logging interval command.

Rate Limiting Syslog Messages:

The logging rate-limit message-rate [except severity-level] command limits the CPU impact of log generation and transmission. This command applies to all syslog messages and is not exclusive to those created through ACL logging. Although this command does limit the number of packets that must be generated and sent by the network device, it does nothing to reduce the number of input packets that are process switched by the device CPU. For this reason, it is imperative that the ip access-list logging interval command be used in conjunction with the logging rate-limit command.

Optimized ACL Logging:

The Catalyst 6500 series switches and Cisco 7600 series routers include hardware support for ACL logging. This feature, known as optimized ACL logging (OAL), was added to Cisco IOS Software version 12.2(17d)SXB and is available on devices that include the Policy Feature Card 3 (PFC3). It should be noted that OAL applies only to unicast IPv4 packets. All other packet types will be logged in software on the Multilayer Switch Feature Card (MSFC).To allow OAL to function properly, the mls rate-limit unicast ip icmp unreachable acl-drop 0 global configuration command must be entered.

Understanding OAL:

Optimized ACL Logging (OAL) provides hardware support for ACL logging. Unless you configure OAL, packets that require logging are processed completely in software on the MSFC. OAL permits or drops packets in hardware on the PFC3 and uses an optimized routine to send information to the MSFC3 to generate the logging messages.

OAL Guidelines and Restrictions

The following guidelines and restrictions apply to OAL:

OAL and VACL capture are incompatible. Do not configure both features on the switch. With OAL configured, use SPAN to capture traffic.

OAL is supported only on the PFC3.

OAL supports only IPv4 unicast packets.

OAL supports VACL logging of permitted ingress traffic

OAL does not provide hardware support for the following:

Reflexive ACLs

ACLs used to filter traffic for other features (for example, QoS)

ACLs for unicast reverse path forwarding (uRPF) check exceptions

Exception packets (for example, TTL failure and MTU failure)

Packets with IP options

Packets addressed at Layer 3 to the router

Packets sent to the MSFC3 to generate ICMP unreachable messages

Packets being processed by features not accelerated in hardware

To provide OAL support for denied packets, enter the mls rate-limit unicast ip icmp unreachable acl-drop 0 command.

CCIE SP Lab Scenarios.

noreply@blogger.com (Murthy) — Wed, 8 Oct 2008 08:29:00 -0700

This website has lot of SP scenarios along with Dynamips NET files. Excellent resource.

http://pwp.netcabo.pt/amsoares/dynamips/dynamips.htm