Xen

If a disk / VDI is orphaned or only partially deleted you’ll notice that under the SR it’s not assigned to any VM. This can cause issues that look like metadata corruption resulting in the inability to migrate VMs or edit storage. For example: [root@xenserver-host ~]# xe vdi-destroy uuid=6c2cd848-ac0e-441c-9cd6-9865fca7fe8b Error code: SR_BACKEND_FAILURE_181 Error parameters: , Error in Metadata volume operation for SR. [opterr=VDI delete operation failed for parameters: /dev/VG_XenStorage-3ae1df17-06ee-7202-eb92-72c266134e16/MGT, 6c2cd848-ac0e-441c-9cd6-9865fca7fe8b. Error: Failed to write file with params [3, 0, 512, 512]. Error: 5], Removing stale VDIs To fix this, you need to remove those VDIs from the SR after first deleting the logical volume: ...

Docker config to setup XO which is a web interface to visualize and administrate your XenServer (or XAPI enabled) hosts Github: sammcj/docker-xen-orchestra Running the app Updates are pushed to the Docker Hub’s automated build service: https://registry.hub.docker.com/u/sammcj/docker-xen-orchestra From Docker Hub docker pull sammcj/docker-xen-orchestra docker run -d -p 8000:80 sammcj/docker-xen-orchestra Building git clone https://github.com/sammcj/docker-xen-orchestra.git cd docker-xen-orchestra # Edit whatever config you want to change docker build -t xen-orchestra . See https://xen-orchestra.com for information on Xen Orchestra ...

Intro At Infoxchange we use XenServer as our Virtualisation of choice. There are many reasons for this including: Open Source. Offers greater performance than VMware. Affordability (it’s free unless you purchase support). Proven backend Xen is very reliable. Reliable cross-host migrations of VMs. The XenCentre client, (although having to run in a Windows VM) is quick and simple to use. Upgrades and patches have proven to be more reliable than VMware. OpenStack while interesting, is not yet reliable or streamlined enough for our small team of 4 to implement and manage. XenServer Storage & Filesystems Unfortunately the downside to XenServer is that it’s underlying OS is quite old. The latest version (6.5) about to be released is still based on Centos 5 and still lacks any form of EXT4 and BTRFS support, direct disk access is not available… without some tweaking and has no real support for TRIM unless you have direct disk access and are happy with EXT3. ...