[c-nsp] Catalyst port groups with trunk ports in between

[Eric Kagan]

We have the following setup, sample config below.
 
We have 2 Data Centers connected via Dark Fiber terminated on Catalyst
switches with GBIC's - Gig port is a trunk.
 
We have a customer with equipment in both locations so we hand him a 100mb
ethernet on his own VLAN.  It been working fine for a year.
 
The customer is pushing the 100mb port and wants 200mb (or GB).  Since these
are Catalyst 3500XL L2 devices I cannot rate limit or police traffic, so I
don't want to give them the 2nd GB port on the switch for fear they will
suck up all the bandwidth (they are doing data replication of terabytes of
data so I could see this happening).  We do not want to upgrade the switches
right now so my idea was add another 100mb port and bond them together.
 
So.......we tried a bunch of different configurations and all hell broke
loose.  They configured port groups on both their switches at each site.  I
tried adding the 2nd FE to the same VLAN 5, no good.  Diff VLAN 6, no good.
I created port groups on both of our switches to see if we could do a
local-local bonding, no good. (We would get either no connectivity across,
VLAN mismatches, Relearn Addr errors, etc).  Are we breaking this by being
in the middle with VLAN's vs. regular ethernet cables ?  Can this work ?
Has anyone ever done this ?
 
If we want to hand then 200mb, what do we need to do on the 2 fiber trunk
switches ?  If I can prove out our side, then they need to prove out theirs.
(The unknown is whether the customer equipment would even work back to back
directly regardless of us in the middle)
 
 
Do all 4 switches need a port group (Side A cust - Side A us - fiber trunk -
Side B us - Side B Cust) where we talk to them at each site with a port
group ?  Do they still need their own VLAN ?
 
or should we be able to just add the 2nd FE to same VLAN 5 ? or hand 2nd FE
on seperate VLAN (i.e. 6) so it looks like 2 diff Ethernet feeds ?

Thanks
Eric
 
 
(Current Config - both sides the same)
 
interface FastEthernet0/5
 description connected to Cust A
 switchport access vlan 5

interface GigabitEthernet0/1
 description connected to fiber-trunk
 switchport trunk allowed vlan 1,2,4,5,6,7,8,12,1002-1005
 switchport mode trunk

 
 
(Additional port ??)    --- ??? same vlan ? diff vlan ?  port group
Cust-Colo Loc A  ???
interface FastEthernet0/6
 description connected to Cust A 
 switchport access vlan 5
 port group 5