...we wanted to upgrade a QM's VM, as we had HA QM's, I explained the admin they could use WMQ' switching mecanism to upgrade VMs without stoping the service...
Anyway the command is :
endmqm -s <QM NAME>
Which makes the active QM switch to the standby instance.
Ok but when I tried to make the switch, I was getting this freaky message AMQ7276 : WebSphere [...].
I was searching a answer to this on google, then I realized the solution was kind obvious :P
...yes, when you wanna switchover, you need to have the standby QM in standby mode, start it with this command : \o/
strmqm -x <QM NAME>