Currently, we routes user to gpfs5(feature) or fallback to gpfs4(default).

There's an user who should've gone to gpfs5 node being route to gpfs4 node. We suspect that it's due to user group lookup failure, and got route to the default side. When an user got migrated to gpfs5, one should not access gpfs4 in any circumstances.

We should make the group lookup explicitly and have no default host, like:

1. feature1
2. feature2
3. other place(look up failure)

We need this new rule to be identical on:

1. ssh-proxy
2. http-proxy
3. slurm job submit plugin