So, you have a xen server, but the virtual machine is not responding, what do you do? You login to the hypervisor and fix it, all right!
Please note for sanitation that random strings have been used instead of real life UUID.
Step 1: Connect Hypervisor
ssh root@somehypervisoriporhostname
Step 2: Check Running Tasks (Task List)
[root@10-1-1-1 ~]# xe task-list
uuid ( RO) : ff9ca1a3-fc29-a245-1f28-2adc646114a2
name-label ( RO): Async.VM.clean_reboot
name-description ( RO):
status ( RO): pending
progress ( RO): 0.371
uuid ( RO) : aff56852-6db4-1ab3-b2b1-33e48c797dbb
name-label ( RO): Connection to VM console
name-description ( RO):
status ( RO): pending
progress ( RO): 0.000
[root@10-1-1-1 ~]# xe task-list params=all
uuid ( RO) : ff9ca1a3-fc29-a245-1f28-2adc646114a2
name-label ( RO): Async.VM.clean_reboot
name-description ( RO):
subtask_of ( RO):
subtasks ( RO):
resident-on ( RO): 43b6096b-09cd-4890-b51b-56e50de573ff
status ( RO): pending
progress ( RO): 0.372
type ( RO):
subtasks ( RO):
resident-on ( RO): 43b6096b-09cd-4890-b51b-56e50de573ff
status ( RO): pending
progress ( RO): 0.000
type ( RO):
I could see that there were two tasks running on this slice:
[root@10-1-1-1 ~]# xe vm-list name-label=slice10011111
uuid ( RO) : 4a9a5dfb-3c4a-b2bb-be7b-db3be6297fff
name-label ( RW): slice10011111
power-state ( RO): running
This told me that the slice was running OK. So I am going to cancel the task pending for it
$ xe task-cancel uuid=ff9ca1a3-fc29-a245-1f28-2adc646114a2
Shutdown the server (HALT IT)
[root@10-1-1-1 ~]# xe vm-shutdown --force uuid=4a9a5dfb-3c4a-b2bb-be7b-db3be6297fff
[root@10-1-1-1 ~]# xe vm-list name-label=slice10011111
uuid ( RO) : 4a9a5dfb-3c4a-b2bb-be7b-db3be6297fff
name-label ( RW): slice10011111
power-state ( RO): halted
Start the Virtual Machine
[root@10-1-1-1 ~]# xe vm-start uuid=4a9a5dfb-3c4a-b2bb-be7b-db3be6297fff
At the end I wanted to check if the instance was still causing a large swap as it was when it was running out of memory! That is the reason why I had to start the server.
(echo "Slice IO_Read IO_Write Total"; (for uuid in $(xe vbd-list params=uuid | awk '$5{print $5}'); do xe vbd-param-list uuid=$uuid | grep -P "^\s*(io_|vm-name-label|vdi-name-label|vdi-uuid|device)" | awk '{if($1=="vdi-uuid") {hasswap="no";vdi_uuid=$4;}}{if($1=="vm-name-label") name=$4; if($1=="vdi-name-label") {if ($4 ~ /swap/) {hasswap="yes";name=name"-swap"}; if ($5 ~ /ephemeral/) name=name"-eph";} if($1=="device"){if($4=="hda" || $4=="xvda") name=name"-root"; if($4=="xvdc" && hasswap=="no") {vdicmd="xe vdi-list uuid="vdi_uuid" params=name-description --minimal | grep swap >> /dev/null"; swpname=system(vdicmd); if(swpname==0) name=name"-swap"};} if($1=="io_read_kbs") ioread=$4; if($1=="io_write_kbs") iowrite=$4}END{if(substr(name,0,9)!="XenServer") print name" "ioread" "iowrite" "ioread+iowrite}'; done) | sort -k4n) | column -t
Job done!