[Monit] Monitor critical processes in radv container

[yozhao101]

Signed-off-by: Yong Zhao [email protected]

Why I did it

This PR aims to monitor critical processes in router advertiser container by Monit.

How I did it

Router advertiser container only ran on T0 device and the T0 device should have at least one VLAN interface
which was configured an IPv6 address. At the same time, router advertiser container will not run on devices of which
the deployment type is 8.

As such, I created a service which will dynamically generate Monit configuration file of router advertiser from a
template.

How to verify it

I verified this implementation on a DuT.

Which release branch to backport (provide reason below if selected)

• 201811
• [x ] 201911
• 202006
• 202012

Description for the changelog

A picture of a cute animal (not mandatory but encouraged)

[jleveque]

Why raise this against the master branch? In master and 202012, we are now monitoring processes using the supervisor-proc-event-listener, and we intend to eliminate process checking by Monit in these branches. Why not raise this directly against 201911?

Also, we need a similar solution for the dhcp_relay container. What is your plan for this?

[yozhao101]

Why raise this against the master branch? In master and 202012, we are now monitoring processes using the supervisor-proc-event-listener, and we intend to eliminate process checking by Monit in these branches. Why not raise this directly against 201911?

Also, we need a similar solution for the dhcp_relay container. What is your plan for this?

Got it. I will close this PR and submit another one against 201911 branch. The new PR will include the change for dhcp_relay .

[yozhao101]

Create a separate PR #7340 to against 201911 branch and include the change on dhcp_relay container.