Colocation to Virtualization

I was changing the VIF interface configuration on a NetApp a few days ago.  I was doing so via command line and outside of an intrusive maintenance window.  The modification was being done on the LAN interface, but the unit also had a VIF that was running production ISCSI data stores.  During this maintenance, only thing that was going to be affected was the snap mirroring through the vif0  interface.  I removed the vif by using ‘vif destroy’.  In doing so, of course the link to the rest of the locations dropped.  After the interface was re-created, I was getting alerts from the console that the remote NetApp connection failed.  The NetApp was accessible locally, was able to ping the gateway, but could not ping outside of the subnet or be reached from other locations.  Coming from a networking background, I knew immediate that this looked to be a gateway issue.  The web interface showed the correct gateway, but ‘route -s’ showed no default gateway.

nas01> route -s
Routing tables

Internet:

Example local ping
nas> ping 172.16.100.1
172.16.100.1 is alive

Pinging the other locations gateway would return with no route to host
ping 172.16.0.1

Add the default gateway in
nas> route add default 172.16.100.1 1

Access restored
nas> ping 172.16.0.1
172.16.0.1 is alive

Verify the routing table
nas01> route -s
Routing tables

Internet:

Note: So it seems that the web GUI just reads the /etc/dgateways from the filesystem.  When I destroyed the vif that acts as the path from the default gateway, it looks to have removed the gateway from the active routing table.  Normally I reboot the whole filer to be safe, but again this was to be transparent to the ISCSI data stores.  Everything worked fine after I manually re-entered the route.  Also, ‘netstat -r’ will also display the routing table.