Is there a procedure (ISR4K, running isr4400-universalk9.16.06.05.SPA.bin) to gracefully shutdown a dspfarm (XCODE mostly) to prepare the router for a reboot/upgrade? I'd like to be able to preserve the active calls and let them drain naturally, but not take any additional calls.
I don't think there is a way to do it on the router. In my situation I have a MRGL with 2 different Resource Groups. I switch the order of the MRGL in Call Manager making the router I want to upgrade lower in the list so its not picked first for calls. This allows the calls to drain off. You could also try removing the resource from the MRG, I don't think that will kill any active calls however if its the only transcoding resource in the group then future calls wont have it available if its needed. However if the router is also rebooting from the upgrade it wouldn't be available for those future calls either so I guess that wouldn't matter. Then after the upgrade put the list back to how they were and you should see it start taking calls again.