Re: Ksplice equivalent for VMS ?

On 2/19/2025 5:26 PM, Dan Cross wrote:

In article <vp5dig$2dnk8$1@dont-email.me>,
Arne Vajhøj  <arne@vajhoej.dk> wrote:

I am thinking about a scenario like:
* cluster with node A and B
* critical process P that for whatever reason does not work
   running concurrent on multiple nodes runs on A
* node A needs to be taken down for some reason
* so VMS on node A and B does some magic and migrate P from A to B
   transparent to users (obviously require a cluster IP address or
   load balancer)

 While this may be an acceptable method to "hotpatch" a host with
minimal disruption to whatever workload it's running, it is
completely unlike what ksplice does.  For one, it requires that
sufficient resources exist in wherever you'd migrate the process
to for the duration of the update.

That is a requirement.
:-)

                                   Moreover, it requires that
all aspects of state that are required to resume execution of
the process are accessable and replicable on other, similar
hardware.

Yes. Which becomes a little easier when restricted to a
cluster instead of any systems.

Many hyperscalar cloud providers do something similar for
updates, but there are serious limitations and downsides; for
example, direct passthru to hardware devices (storage, compute
accelerators, etc) can make it impossible to move a VM.

Moving VM's is common. Robert started by mentioning vMotion.
Arne