Hi, I'm using CS 4.0.1 and XS 6.0.2. There is a problem with taking snapshots of instances.
Some of VMs have scheduled snapshots (e.g. weekly, monthly) so eventually there will be quite some number of snapshots on secondary storage. This is fine as I read CloudStack should copy snapshots to secondary storage and then coalesce snapshots on primary storage so can keep the chain not too long (like 3-4 child normally). However I found after snapshot been taken for a while it starts failing due to error logged on CS Management log 'SR_BACKEND_FAILURE_109The snapshot chain is too long'. I verified it by checking with vhd-util and it does show the affected VHD has exactly 30 snapshots in chain which is the limit for XenServer. I tried to search for info why the chain can grow to 30 and only found this article for CloudStack 2.2 http://support.citrix.com/article/CTX133470 seems to be related. It mentioned there maybe problem preventing XenServer from cleaning up snapshots. However I can't find any more error info other than CS Management log 'SR_BACKEND_FAILURE_109The snapshot chain is too long'. What can cause XenServer or CloudStack not cleaning up snapshots from primary storage? Thanks in advance. Yong
