Tuesday, July 29, 2008

VMware Consolidated Backup 101

So when you have to rebuild/upgrade your Virtual Center don't forget to add your VCB user at the top of your cluster , which will allow the VCB user to mount and snapshot the VM's your trying to backup.

The permission will inherit all the way down the cluster through to the hosts so you should only need to apply it at the top level.

Sunday, July 27, 2008

Eat those Snickers Fool

Friday, July 25, 2008

Happy Sys Admin Day

Happy Sys Admin Day

Hope you get lots of thanks , and if your lucky some chocolates and maybe even a few beers

Monday, July 21, 2008

VMware VCB Backup Issues

So I've got a few Vm's which are getting backed up via VCB via a Commvault Proxy (file level backups only). And I must say when it breaks it breaks wonderfully , troubleshooting it can be a tedious task , here are some things to check..

1. Make sure your HBA's have the lastest drivers.
2. Make sure your ESX Cluster has the latest patch's
3. LUN Masking and zoning information are correct ie the VCB Proxy host can see the same LUN's as the ESX cluster , and the LUN id's appear the same in windows as they are number in the array.
4. Also check your backup vendor has any updates/scripts for VCB (I didn't have to update these scripts yet , not until the cluster is on ESX 3.5

Wednesday, July 16, 2008

Funny Google AD

Thursday, July 10, 2008

Sun's New Thumper X4540

Tuesday, July 08, 2008

YouTube Scalability

An interesting talk about how the orginal guys who started YouTube built it , and the issues they faced.

Monday, July 07, 2008

Diablo 3

Man I remember spending way to many hours on this game back when I should have been studying.

Mac Vs PC Vs Linux

RAID 5 Write Hole

I've been spending a fair bit of time reading up on ZFS and came across a term called the "RAID 5 Write Hole" and this is what it means , explained from the father of ZFS Jeff Bonwick.

“RAID-5 (and other data/parity schemes such as RAID-4, RAID-6, even-odd, and Row Diagonal Parity) never quite delivered on the RAID promise – and can’t – due to a fatal flaw known as the RAID-5 write hole. Whenever you update the data in a RAID stripe you must also update the parity, so that all disks XOR to zero – it’s that equation that allows you to reconstruct data when a disk fails. The problem is that there’s no way to update two or more disks atomically, so RAID stripes can become damaged during a crash or power outage.

“To see this, suppose you lose power after writing a data block but before writing the corresponding parity block. Now the data and parity for that stripe are inconsistent, and they’ll remain inconsistent forever (unless you happen to overwrite the old data with a full-stripe write at some point). Therefore, if a disk fails, the RAID reconstruction process will generate garbage the next time you read any block on that stripe. What’s worse, it will do so silently—it has no idea that it’s giving you corrupt data.”

Friday, July 04, 2008

TF2 Goes Female