Re: [DISCUSS] CloudStack graceful shutdown
I may be remembering this incorrectly, but from what I recall, if a resource is owned by one MS and a request related to that resource comes in to another MS, the MS that received the request passes it on to the other MS.
> On Apr 4, 2018, at 2:36 PM, Rafael Weingärtner <rafaelweingartner@xxxxxxxxx> wrote:
> Big +1 for this feature; I only have a few doubts.
> * Regarding the tasks/jobs that management servers (MSs) execute; are these
> tasks originate from requests that come to the MS, or is it possible that
> requests received by one management server to be executed by other? I mean,
> if I execute a request against MS1, will this request always be
> executed/threated by MS1, or is it possible that this request is executed
> by another MS (e.g. MS2)?
> * I would suggest that after we block traffic coming from 8080/8443/8250(we
> will need to block this as well right?), we can log the execution of tasks.
> I mean, something saying, there are XXX tasks (enumerate tasks) still being
> executed, we will wait for them to finish before shutting down.
> * The timeout (60 minutes suggested) could be global settings that we can
> load before executing the graceful-shutdown.
> On Wed, Apr 4, 2018 at 5:15 PM, ilya musayev <ilya.mailing.lists@xxxxxxxxx>
>> Use case:
>> In any environment - time to time - administrator needs to perform a
>> maintenance. Current stop sequence of cloudstack management server will
>> ignore the fact that there may be long running async jobs - and terminate
>> the process. This in turn can create a poor user experience and occasional
>> inconsistency in cloudstack db.
>> This is especially painful in large environments where the user has
>> thousands of nodes and there is a continuous patching that happens around
>> the clock - that requires migration of workload from one node to another.
>> With that said - i've created a script that monitors the async job queue
>> for given MS and waits for it complete all jobs. More details are posted
>> I'd like to introduce "graceful-shutdown" into the systemctl/service of
>> cloudstack-management service.
>> The details of how it will work is below:
>> Workflow for graceful shutdown:
>> Using iptables/firewalld - block any connection attempts on 8080/8443 (we
>> can identify the ports dynamically)
>> Identify the MSID for the node, using the proper msid - query async_job
>> table for
>> 1) any jobs that are still running (or job_status=“0”)
>> 2) job_dispatcher not like “pseudoJobDispatcher"
>> 3) job_init_msid=$my_ms_id
>> Monitor this async_job table for 60 minutes - until all async jobs for MSID
>> are done, then proceed with shutdown
>> If failed for any reason or terminated, catch the exit via trap command
>> and unblock the 8080/8443
>> Comments are welcome
> Rafael Weingärtner