Instant Gratification

ML 115 RAID nightmare

2013-02-25T02:11:00.005-08:00

Recently the ML115 that I had bought for my cousin had thrown up an error!

It complained that the mirror is now degraded and when I explored further, one of the disks needed replacement. Now as you would expect with any sensible RAID controller, once the replacement is done, rebuild is automatic. But here, things are different:

- the raid is not full featured raid hardware
- you need software support to rebuild RAID
- OS crashes if you try to add a new drive in place of the faulty drive
- this version of nVidia MediaShield does not work with any OS you know of / I fail to get the requisite software through HP resources.
- researching for this kind of options is a big waste of time as they are not very apparent, which I learned after I did waste a lot of time

Solution:

Rather than looking at (rather impossible) rebuilding the RAID; I have done this to quickly come to a solution;
- take a backup of entire healthy disk onto a tape / external media.
- replace the faulty hard disk
- delete the array
- create a new array
- restore entire contents from the backup
- install / upgrade / repair OS as the need may be.

While the search for a solution was long; once I knew the alternative, it was pretty quick, about 6 hours to get it to sanity.

Lesson:
Use software RAID sparingly; Suggest only if the user / you have time to accommodate any failure / recovery situations.
A hardware RAID is worth the money.

ESXi host with a economy of space and money

2013-01-22T19:32:00.000-08:00

I realize that new Macmini with its capacity to host as much as 16GB RAM and hold 2 hard drives is a good candidate for low load multi-VM situations (Testbeds / Personal use / SOHO Startups) using ESXi.

With the new Macmini5,1 on hand, tried to see what can be done with this, apart from the on-board Lion. Migration from the old Macmini3,1 was a breeze. I had used a crossover cable to maximize throughput as my home switch restricts transfers of the much abler SSD source and target.

Lion seems to have taken out compatibility for PowerPC apps and I had to reinstall a couple of Apps.

However, the real fun was using this as an ESXi host. The steps are captured here:

Download recent ESXi 5.1.0.
Burn it to a disc using a USB CD/DVD writer.
Grab an 8GB usb stick for the ESXi installation target. (I did not want to mess up my Lion.)

Boot from CD/DVD that was burnt by pressing C during boot. Alternately, this shows up on (Alt/Option) boot selector as "EFI Boot"

Caveat:
Note that Boot device selection from Bluetooth Keyboard may not work as the Bluetooth communication seems to kick off after the Boot device selection on the Mac.

Use a USB keyboard for the Boot selection to be sure. Use of BT device may fail to boot your system.

The installation of ESXi is straight forward, except that you have to verify that the capacity and name of the device that you are installing to. Keep a watchful eye so you do not overwrite your Lion.

After the install, eject the CD/DVD; boot from USB stick which shows as "EFI Boot" on boot selector.

Now ESXi just boots fine, but I see that it did not pick up DHCP address, so something wrong here. I did a search to find that a driver update would be needed to make this work.

I rebooted to Lion, downloaded the new Broadcom driver offline bundle from https://my.vmware.com/group/vmware/details?downloadGroup=DT-ESXI50-Broadcom-tg3-3-120h-v50-2&productId=229

This downloads a zip file, and was automatically unzipped into a directory tg3_3 on the mac. this directory has a a file tg3-3.120h.v50.2-offline_bundle-547149.zip, which needs to land on the esxi live path "/var/log/vmware" .

Notice that the USB stick is mounted as three volumes on the desktop.
Two of these are redundant boot partitions with just a coupe of files visible from OS X, with the other hosting a filesystem.

The easiest way is to copy this file to one of the two boot partitions.

Reboot into ESXi, turn on the ESXi shell in the Maintenance settings.

Locate the file *zip in the root folder of one of the boot volumes,
copy that to /var/log/vmware

Now, run the command

esxcli software vib install --no-sig-check --maintenance-mode -d /var/log/vmware/tg3-3.120h.v50.2-offline_bundle-547149.zip

There is a chance that tg3-3.120h.v50.2-offline_bundle-547149.zip may be in CAPS. In case it is, just change the capitalization as it is in the above command.

After the install is finished, reboot into ESXi and see that it picks the DHCP address now. "Test Management Framework" to see that the connectivity is proper.

Now it is your choice to restore Lion to an external disk and use the internal disk as an ESXi datastore. or mount a network store for hosting your images?

Determining Memory Installed in a ESXi 5 host

2013-01-22T19:21:00.001-08:00

The new interface for ESXi 5 omits the detail that the previous version had on the hardware installed. Recently I had to see how the memory slots are filled in my server.

cim-diagnostic.sh | grep -A30 "OMC_PhysicalMemory" | grep -v "NULL"

gives a picture of the memory modules installed with their speed, capacity and type. This helps in easily finding a match for them or upgrade.

Hibernate a Mac Mini

2012-12-30T08:51:00.001-08:00

Once you have an SSD to ensure quick disk response, it is worthwhile to have hibernate enabled. This will help you to keep the work threads continued. If you want to do this once in a day / on less used Mac Mini / iMac at home: sudo pmset -a hibernatemode 25 However at work, where you leave your desk only for a few minutes at a time, it is good to use restore from memory as this is quicker and saves some power as well. You can realize this using: sudo pmset -a hibernatemode 3

Application specific passwords and SSO

2012-09-20T22:43:00.003-07:00

Ever since I had first registered to Yahoo 14 years ago, I had changes the password multiple times to keep myself immune. Recently, I had to check my mail at a public computer and the very next day, before I changed my password, noticed that there is a lot of spam generated from my account. On digging details, get to see that a Chinese IP is relaying spam on my name. A trojan stole my key punches. I had seen that Yahoo had recently introduced a two-way authentication for non-primary clients with mobile as the second factor of authentication. Activated this to control damage. Further investigation on Google shows that they have implemented a beautiful means of application-specific authentication: http://support.google.com/accounts/bin/answer.py?hl=en&answer=185833 This means, that you can control relay from any of the devices/applications that you use. Essentially, this means that you can enjoy the Single Sign On with you protecting the Master Password. Client/Device specific passwords should be the norm for all Mail servers as this would give absolute control on relay. SPF on both relay server as well as the recipient side, sender authentication for each relay, device specific passwords would ensure most of the impersonation is taken care off. With all due respect to the SSO, these are basic issues to be addressed in similar apps. Review of metrics is very important even after the implementation of Application Specific Passwords as you would never know if a device is cracked.

NFS connection from OS X client to Linux server

2012-08-11T03:54:00.001-07:00


On server:
/etc/exports will have 
/home/              ipblock/24(rw,insecure)
exportfs -a


On client:
sudo mount_nfs -P :/home/ 


Ensure that user ids are the same on both server and client, unless using a centralised auth server.

Locating your Apple Devices

2012-07-04T23:28:00.001-07:00

Tried out this feature today. Works beautifully. https://www.icloud.com/#find

Importance of Vision

2011-07-29T05:09:00.000-07:00

Interesting read...

http://altdevblogaday.com/2011/07/28/the-importance-of-vision/

Hewlett Packard sues Oracle over Itanium chip dispute

2011-06-16T10:05:00.000-07:00

Hewlett Packard sues Oracle over Itanium chip dispute

This is an interesting case: of what is possible with monopoly.

With the cores and threads going up each day in the regular processors, there is less need for alternatives, and my choice would never be one of Sparc / Itanium either. Intel /AMD are most sensible as of now with attractive prices and power.

Check tho, Oracle's Roadmap for Sparc and decide for yourself :)

Let me see how true Oracle proves of my expectation: What if Oracle buys Sun.

Buying a MacBook Pro

2011-05-31T03:37:00.000-07:00

I have finally resolved to buy a MacBook Pro!

For various reasons : its stability, UI, formidable OS X, the command line which lets me navigate around with the BSD feel.

Now the price is something that I want to checkout. I just compared the prices to see that most Apple products are costing 20-30% more in India than the US. Rationale for the price aside, I just decided to ask one of my friends to fetch it for me. Of course it is always a barter :)

The best place to pick up a mac would be (if you have friends there): Delaware, Montana, New Hampshire, Alaska, Oregon as these states have minimal sales tax.

Students have a chance to avail education discounts, this may be about 10% off the list price.

What options do I have?

Refurbished products: These give me 15-20% off the list price.

Positives of Refurbished products:
Not so attractive packaging, so you can discard it and save a lot of space :)
Deep discounts
Best price for a mac, with same performance
Comes with warranty just like the regular product

Negatives:
Can only be ordered online
Not for those who want the "Only my hands first on the box" types
Generally old configurations from last one or two years appear here.

But, if I have a regular product listed here with the same deep discount, why would I not buy it? Or anyone else, unless they are dumb as an ...

So I just thought one app such would help myself to have a quick look each day if there are good enough offers like here:

http://mykin.in/best-macs/best-macs-best-price.php

So effectively, I could manage a discount >25% on the list price in India.
Worth the effort, and looking for the MBP to arrive.

Swat ?!

2011-05-11T22:54:00.000-07:00

"In Swat, there was a time when we saw the army and the Taliban running their respective checkpoints literally yards away from each other," says Abdur Rab, a resident of Mingora. "People used to say, where there is army, there would be Taliban."

Surprisingly the above statement touches even an extreme angle vis-a-vis the public image of Pakistani army trying to crush Taliban in Swat. My impression was that Taliban was trying to be too aggressive.

Are the Pakistani military in a corrective mode at least now? The recent events seem to suggest that; after they had been seeing a lot of internal strife and killings owing to hosting the fugitives. But with people who live for a revenge alone rather than progress from within, it is hard to estimate.

Ghantasala Songs

2010-06-10T07:58:00.001-07:00

A beautiful compilation of all old songs which are out of the copyright period along with lyrics for some. Enjoy!

http://www.ghantasala.info/

UFO encounters

2010-02-19T20:34:00.000-08:00

Mysteries never fail to attract the attention of people :)

SOHO server : ML115 from HP and FreeBSD

2009-12-28T21:30:00.000-08:00

Recently, I have bought an ML115 for my cousin for his office with 1TB RAID5, 4GB RAM, 2 network interfaces, all in just about INR 35000. Headless of course.

This is a powerful server for small businesses / fit to be your home desktop as well if you worry about your movies, songs and years of data lost in a hard disk crash.

This runs my choice Server OS: FreeBSD. The ServeRAID configures beautifully.

This server runs NAT, DNS, DHCP, Squid, Fileserver, Mailserver, SVN Server and Wiki. The beast can not be heard 'breathing', except when you put it down and wake it up. Packs in anti-virus protection, spam-protection at no extra cost.

Simply put, this is their cheap UTM(Unified Threat Management) device + multiple servers clubbed into one below USD 1000. My services are free for my cousin tho :)

When you compare this to any UTM device,
1. It is as good as any other solid state devices as long as the power supply is sane and un-interrupted. More than one FreeBSD servers I had configured previously is running non-stop for the last five years.
2. It does not just use third party BLs to reject mails. It does not believe in shortcuts and hence lose small timers or non-tech savvy clients who may be looking at our services. A mail bouncing on their face is not a healthy way of starting a relationship. It just sorts out any potential risks / spam into another folder.
3. You have detailed logs on everything and you have toolset available to make it more useful, which is not so with a UTM. And most of these cost in the range of USD 4000, technical support over phone provided of course, trying to teach a non-techy guy routing.

I would continue to recommend this server, ML115 for replacing UTMs.

Protecting sshd from brute-force attacks

2009-12-28T21:02:00.001-08:00

One may use GeoIP's database and the tcp-wrappers to block attacks from rogue networks. If you know that the ssh logins can be restricted to a country / countries, you may be able to block most brute-force attacks by using MaxMind's GeoIP database.

All you need to do is
1. modify your /etc/hosts.allow

stop all services being unblocked:
#ALL : ALL : allow

unblock sshd for IPs:

sshd : 127.0.0.1: allow
sshd : /etc/hosts.sshblock : deny
sshd : ALL : spawn ( /scripts/sshIN.sh %a ) &

/etc/hosts.sshblock will contain the list of all blocked sites.

##/scrips.sshIN.sh starts
#!/bin/sh
country=`/usr/local/bin/geoiplookup $1 | /usr/bin/cut -f4 -d" " | /usr/bin/cut -c1,2`
if [ "x$country" = "xIN" ]
then
return 0
else
echo $1 >> /etc/hosts.sshblock
return 1
fi
##/scrips.sshIN.sh ends

You may replace the country name as required.
This script allows known IPs from India only and blocks all others from the second effort onward. You still have one chance to login from an unlisted IP if it is not blocked previously. IP-spoof can be an unaddressed problem here. Need to work on it.

You may certainly deny access to selective countries as well, changing the code to suit your requirement.

The same logic applies to other services as well.

What a leader can do

2009-12-28T06:01:00.000-08:00

10-15 years ago, we have seen a head of government toil day in and out to bring in business and drive the primarily agrarian economy to speed towards IT services and was successful in developing a great brand for Hyderabad.

In his time, the media was talking of making Hyderabad another Singapore and he was rightfully seen as a visionary everyone respected. The state of Andhra Pradesh earned a lot of envy from across India. And the leaders of states developed a healthy competition in attracting business to their respective states.

The other thing that you need to appreciate about this guy is that he managed water as well in the same spirit ensuring good harvest in times of drought.

This leader was projected as
1. anti-farmers
2. anti-public servants
Both these are big and influential groups deciding electoral wins.

Putting people against a person based on his following traits pushed him down.
1. loose words at one-time
2. the CEO of AP's follies with basic management of teams i.e.
You should skip levels down to positively motivate teams.
You should never use direct pressure skipping levels down. This will demotivate and insensitize all levels down to pressure.

Thus, a promising leader had to lose his role and retire out of public life. His efforts to be a constructive opposition leader were ridiculed and met with brutal put-downs, which distanced him from active participation.

Then another leader who reached out to the masses and said, it is only a few that are reaping the benefits of IT boom, and more needs to be done to farmers, caught all the limelight and usurped power from the previous one.

This guy certainly had great dreams, but with no grounds. He certainly is a good leader, but no good administrator. His times saw ambitious plans, but little productive execution and a lot of corruption.

This led to another leader use the hate-propaganda to achieve his aims. He is successful in putting people against people inciting them with small detail that differentiates people. And branding people as looters and looted.

Now no one makes an identity for himself doing something unique and useful to the society at large. It is now a question of what region you are from.

Does this differentiation stop with state? district? religion? which side of the river? which side of the mines? what slang you speak? how many insults you can throw at the other?

All the difference over the years is because of leadership. Or lack of positive leadership traits in the leaders? Or people who dare not speak about what is wrong with a leader?

Now there is no one dream compare Hyderabad as reaching anywhere near Singapore, leave alone reach out to the other metros in attracting business.

Negative energies are always strong? Or do we lack leadership that champions the truth? Where are we heading? Only time will tell us.

PHP to walk thru the Active Directory structure

2009-10-11T08:38:00.000-07:00

//Set the Active directory Servers and the FQDN here
$AD_SERVERS = array( "pdc.domain.com", "mdc.domain.com" );
$FQDN = "domain.com";

//See if the servers are available
foreach ($AD_SERVERS as $AD_SERVER) {
if (! $ds) $ds=ldap_connect($AD_SERVER);
}

if (! $ds) $error_msg="Apologies. Can not Contact Authentication Servers!";

// See if auth credentials supplied from the login page are proper
$name=$_POST[loginname]."@".$FQDN;
$password=$_POST[password];
$searchuser="SAMaccountname=".$_POST[loginname];

//Refer all users and groups active and disabled
//$searchuser="SAMaccountname=*";

$r=ldap_bind($ds, $name, $password ) ;
if ($r != 0 ) {
// May need to change this info based on specific implementation of Active Directory
$sr=ldap_search($ds, "ou=Accounts, dc=domain, dc=com", $searchuser);
$info = ldap_get_entries($ds, $sr);

for ($i=0; $i<$info["count"]; $i++) {
echo "<table border=1>";
for ($x=0; $info[$i][$x];$x++) {
$attrib=$info[$i][$x] ;echo "<tr><td>" . $attrib. "</td><td></td></tr>";
$count=$info[$i][$attrib][count];//echo "Count: ". $count. "<br />";
for($y=0;$y<$count;$y++) echo "<tr><td></td><td>" . $info[$i][$attrib][$y] . "</td></tr>";
}
echo "</table>";
}
ldap_close($ds);
}

Living by Nature

2009-10-11T08:22:00.000-07:00

This looks like a very promising proposal:
http://news.bbc.co.uk/2/hi/programmes/click_online/8297237.stm

May be future server racks should support special water cooling mechanisms to reduce cooling requirements?

Also, having
1. the deserts filled with solar panels and other heat-electricity devices
2. shores driving mills using the water forces
3. peaks hosting wind turbines
will not be such a distant dream?

Vedic Math

2009-09-26T04:10:00.000-07:00

Some exercises in Vedic math:

http://www.hinduism.co.za/vedic.htm

"There is something to learn from everyone - Sometimes in terms of what not to be."

2009-09-08T05:27:00.000-07:00

Thus says a friend!

Akshaya Patra

2009-08-18T06:07:00.000-07:00

Taking cue from Krishna Priya (she is on my contact list in Linkedin), I started hosting a few sweets on my desk for the last few weeks. I used to keep filling it. I saw that people found it useful to ease out their stress with a little quick sugar pumped into their system and some small talk.

For the last few days though, I could not refill the container. And here comes the surprise! People started filling in.

What I see out of this is that some good practices die hard.

It is what you spread around, that is seen around. If you want your teams feed goodwill to you, you do it to start with.

You can see the same in other areas as well, be it transparency in operation, upright discussion on personal / professional problems. Being in the {solution} is always good rather than the {complaining}.

And finally, what do we call this idea?

Akshaya Patra as it has something to give everyone involved?

BTW, I am filling it back again.

Sugar and the options

2009-08-06T05:01:00.000-07:00

${SUGAR}/include/language/en_us.lang.php

has all the strings for drop-down menus that you need to change for the English Language. Customise to your req.

Howto replace Inbox with blackberry mbox on a nokia e61

2009-07-25T19:32:00.001-07:00

Tools > Settings > Phone >Standby Mode > Active Standby Mailbox : Select your fav. mailbox

You may also customise what you want on your home screen by selecting the active standby apps.

Sending HTML Massmailers using a shell script

2009-07-24T23:22:00.000-07:00

Tool required: mutt 1.5+

Configure mutt for html send and the sender address you want to use.

==
vi ~/.muttrc
set from="myaddress@my.domain"
set realname="My Full Name"
set content_type="text/html"
==

Build the html into target.html, probably with a unique image for campaign and the target email id as an argument to trace responses.

cat target.html | /usr/local/bin/mutt -e 'set content_type="text/html"' -s "Subject of the Mailer" $itemOfTheEmailList

Mutt helps to inject the content-type header into the mail an also helps with attaching stuff to the mail with a "-a" option.

Marketing mailers should ideally be short html with references to the web content.
The web references help analyse the target demographic and responses tied to specific campaigns.

To know of the visitors who saw the mail, script similar to the one below helps

grep "GET /?mailid=" /var/log/httpd-access.log | cut -f2- -d'=' | cut -f1 -d" " | sort | uniq

Swat and the criticality

2009-04-22T22:09:00.000-07:00

Looking at the way fundamentalists are taking control of Swat and neighboring areas, it is a serious point of concern for India.

Why?

The geographic location of the area connects Afghanistan-PoK-and Kashmir Valley.

This means that the guerilla forces would have had a good area under them where from they can launch strikes and vanish into the rough terrain and restrike. This would mean that once they have complete control of this area, no single state can control them for reasons well-known as the area spans over countries.

This means, the whole of South Asia will be seriouly affected and with not so friendly states around, the fundamentalists can use the leverage to strengthen their presence. This may mean return of the 80's and 90's to the Kashmir Valley and not so pleasant news on news channels on a daily basis.

How are states affected?

Afghanistan may be the first to fall with the fundamentalists having bases to the East and South of Kabul and with now not so committed Allied forces (since they are fighting there for years) it may stand a bigger risk.

Pakistan will finally go the way of Talebani Afghan trying to find its own confused identity. This is evident from the inefficient way the weak Pakistani Government handled the Swat disturbances. With ample support from the ISI and the military Taleban may not find it hard to reach the seat of power in Islamabad.

The biggest concern here is how the world responds or tries to prevent the Taleban from reaching the Nuclear Arms.

India will have to face a proxy / guerilla war as it had faced for a long time and an added threat of Nuclear Arms in the hands of people who can do anything in the name of Religion.

It is absolutely not a time to sit idle and watch it as fun show in the neighborhood.

US may find a more bullish enemy with nuclear arms, unlike the case of Afghanistan, where it is just guerilla warfare with traditional arms.