...

When should I turn off Dynamic Discovery? (#TODO)

What is the process for seamlessly upgrading a router?

To upgrade a router with minimum impact to the live system use the following steps:

1. Make sure there's more than one router in the system and that they can handle the load if one router is decommissioned
2. Unload Lnet modules on the router to be reconfigured.

3. On the nodes connected to and configured to use this router,

   Code Block
   lnetctl route show -v 4

   should show that the router is down. Remote LNet ping should succeed because other routers should get used instead:

   Code Block
   lnetctl ping <remote nid>

4. Make changes to the decommissioned router configuration and bring it back online.

5. On the nodes connected to and configured to use the router, 

   Code Block
   lnetctl route show -v 4

   may show that the router is still down. In that case, rediscover the router:

   Code Block
   lnetctl discover <router nid>