Hi all,
I'm in a situation that i must stretch l2 between datacenters for server migration purposes.
Current:
Location1 - stretch network - LocationNEW
The first location is running RPVST+. The migration network (Cisco4900M switches) we also configured for RPVST till the boundary at the new network. We have 2 uplinks from location1 to the stretch network (The switches in location 1 are the spt root for all the vlans on the stretch) and with normal spanning-tree root bridge selection we load balance the vlans between the 2 uplinks fron the stretched network towards Location1 .
Desired situation :
Attach Location2 with 2 uplinks to the stretch to start also the server migration from Location2 to the LocationNEW.
Location1 - stretch network - LocationNEW
Location2 - stretch network - LocationNEW
The Location2 network is running MSTP. Ive read a lot of documentation on the network and it seems to interoperate without problems between the 2 protocols (MST & RPVST+). Ive NO VLAN OVERLAP between the networks. Lets say i want to stretch vlan 100-110 from this Location2 network to the LocationNEW. I make sure that de IST (Instance0) bridge-id is the lowest in the MST network AND stretch network. Ive read that at the boundary on the MST region only the IST BPDU's are replication on all vlans allowed on the trunks. (In my example vlan 100-110). Then from the stretched network (RPVST+) one port will be blocking and one port will be forwarding towards the MST region (Because the CST BPDU's are the lowest=best). (From the RPVST+ perspective the whole MST region is 1 virtual-bridge). On the uplinks from the stretched network towards location2 i can enter spanning-tree per vlan port cost to archive load-balancing. (For example vlan 100-105 takes the first uplink and vlan 106-110 takes the second uplink).
I got 2 questions:
-Am i right?
-Currently on the stretched network (I'm just starting here at the new client and i dont know the reason for this yet) they entered the command "no spanning-tree vlan 1". Vlan 1 is the native vlan on all trunks.... Is this causing for any problems in my setup? The documentation is very confusing on this part.....
I hope you can help me :-)
Kind regards,
Stefan
