Hi All,
Started at a new company recently and they’ve had a ongoing issues for ages where they could only access one of two switches in their server room if they were on the same subnet.
So Switch A was the problem switch and had a IP of 10.0.0.123,
Switch B they could access from anywhere and had a IP of 10.0.0.124.
My Computer had a IP of 192.168.111.1.
So initially I started thinking the issue was down to vlans as we have around 50 vlans and I kind of just presumed it would be a issue with cross vlan routing. Well actually I was wrong.
Firstly I pinged both switches:
SwicthA – Can not ping.
SwitchB – Can ping.
Next Trace route (TraceRT from a win 7 PC)
SwitchA – Could not trace
SwitchB – two hop trace, Core switch then the switch.
Ok so what next…..Lets try the above from the switches (so after connecting to server on the same subnet I ran the tests):
Ping my PC:
SwicthA – could not ping,
SwitchB – could ping.
Trace route:
SwitchA – No route,
SwitchB – two hop route.
So after this I decided it must be a routing issue, as both switches could ping the core switch and both switches could trace route the core switch. So lets have a butchers at the routing.
Switch A# show ip route IP Route Entries Destination Gateway VLAN Type Sub-Type Metric Dist. ------------------ --------------- ---- --------- ---------- ---------- ----- 10.0.0.0/8 DEFAULT_VLAN 1 connected 1 0 127.0.0.0/8 reject static 0 0 127.0.0.1/32 lo0 connected 1 0 192.168.101.0/24 iSCSI-VLAN 1010 connected 1 0
Switch B# show ip route IP Route Entries Destination Gateway VLAN Type Sub-Type Metric Dist. ------------------ --------------- ---- --------- ---------- ---------- ----- 0.0.0.0/0 10.0.0.2 1 static 250 1 10.0.0.0/8 DEFAULT_VLAN 1 connected 1 0 127.0.0.0/8 reject static 0 0 127.0.0.1/32 lo0 connected 1 0 192.168.101.0/24 iSCSI-VLAN 1010 connected 1 0
Hold the phone, there’s no sodding return route to the core switch (10.0.0.2)
So I added the route like so:
Switch B# conf Switch B (conf)# ip route-static 0.0.0.0 0.0.0.0 10.0.0.2 Switch B# write
And bobs your uncle it worked!!
