Xenserver 6 – Create an Addtional Local Storage Respository with Thin Provisioning Support

ShippingSo recently I deployed 3 XenServer 6 hosts with local storage only. Our need was to virtualize approx 6 very old Centos QA servers running on ancient hardware.

Since I did not have any dedicated network/san storage at my disposal I stuck 6, 146 SAS drives in each server and carved them up into a 410GB raid 10 array.

However the XenServer install did not detect this secondary logical disk, so I had to figure out how to manualy create a storage repository using this new drive.

The first thing that I needed to do was to see how the disk was identified by the OS, for this I used fdisk

#fdisk -l

Disk /dev/sdb: 440.3 GB, 440345714688 bytes
255 heads, 63 sectors/track, 53535 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Using the output above I was easily able to determine that my secondary drive was /dev/sdb.

So first this i did was to determine the UUID of the host that I was logged into

xe host-list

Which spit out the output below

# xe host-list
uuid ( RO) : 4a9971f7-1e59-4e02-b849-04d206ee7b2b
name-label ( RW): xen01
name-description ( RW): Default install of XenServer

Then I ran the following command to create my new SR on /dev/sdb on xen01

xe sr-create host-uuid=4a9971f7-1e59-4e02-b849-04d206ee7b2b content-type=user type=ext device-config:device=/dev/sdb shared=false name-label=”Local storage 2″

Then I confirmed that the new SR was created

xe sr-list host=xen01

Note that one fo the things that I found most odd with this process is that you do not actually create a partition on your disk before turning it into a storage repository.


LSI MegaCLI — Check For Failed Raid Controller Battery

701590_rusty_batteryThere are several tools that you can use to monitor and configure and LSI SAS controller, however as I have found, some are easier than others to use and some do not always display the correct information.

In my case my controller is a SAS 9260-8i, and when building a server I always make sure that I install the MegaRaid Storage Manager gui for configuring disks and setting up email alerts. However I have often found that this tool is sometimes confusing to use for other tasks so I also make sure that I install the MegaCLI (command line interface). Both utilities can be downloaded directly from LSI here.

MegaRaid Storage Manager installs to /usr/local/MegaRAID Storage Manager, while the cli installs via rpm to /opt/MegaRAID/MegaCli.

Anyway to check the battery status run the following (note i am running 64 bit os)

#>./MegaCli64 -AdpBbuCmd -aAll

Your output will be lengthy – but look for the line below to know if you need to replace your BBU.

Battery Replacement required            : Yes

Two additional usefully commands are:

  • 1
    megacli -AdpAllInfo -aALL

    lists all the adapters in the machine

  • 1
    megacli -PDList -aALL

    lists all disks and enclosures

Note that there is an open source CLI called Megactl, and while its quick and easy to use to see a quick list of your disks and their statuses, its not shown itself to be accurate when it comes to detecting whether or not a battery has failed. You can get it here

Additonal Megacli command can be found here; https://twiki.cern.ch/twiki/bin/view/FIOgroup/DiskRefPerc