A Citrix XenServer host that is managed by Apache CloudStack will reboot itself along with all running virtual machines running on the host if there is a problem with the primary storage after a period of time. In general this is a good protection method, if the primary storage is no longer available it can cause problems for the virtual machines, Windows VMs may blue screen of death (BSOD) while Linux VMs may enter a read only file system state to protect against data loss. However you may have multiple NFS mount points to act as primary storage and may not want every VM on the XenServer host to power off with the host should this happen. It is possible to work around this by modifying the heartbeat script created by CloudStack on the XenServer host.
Tag Archives: Apache CloudStack
Recently while trying to boot from an ISO in Apache CloudStack I received the error “Unable to start instance ‘hostname’ (UUID), see management server log for details”. The ISO media did not support installation as a PV guest in XenServer 6.2, it needed to be installed in PVHVM mode which required the following work around in order to boot correctly.
In Apache CloudStack it is possible for the database to become out of sync with what is actually happening. For instance if there is a network issue preventing CloudStack from correctly connecting to the hypervisor or virtual machine and you try to shutdown or reboot a server, the action may not actually take place despite the state in the CloudStack database being modified.
This can cause the instance to show as being in the ‘starting’ or ‘stopping’ states for instance, however the virtual machine may already be fully booted or completely powered off. To fix this we can manually update the management database to the correct state.
While trying to transfer templates within Citrix CloudPlatform (Apache CloudStack) between different zones I received the below error:
sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
This post covers how to fix this.