Get Creative: Static Routing with Catalyst 3750
Here's an interesting scenario:
We have two sites, each using a Catalyst 3750 switch, and routing between them using static routes. There's a primary fiber link between them and we're using twisted-pair-to-fiber converters due to port limitations on Cat3750. These converters do not report fiber link down status correctly (the carrier is still present on twisted pair even if fiber is down), so the primary Ethernet interfaces do not go down if the fiber link breaks and the primary static route is not removed, requiring manual action to switch over to the backup link.
The setup is summarized in this diagram:
Network diagram
My initial reaction was a polite answer explaining that the dynamic routing protocols were invented to handle scenarios like this one, but the poor guy responded that "his boss does not want to hear about a dynamic routing protocol."
I've got a few other ideas in the meantime (at least one of them working perfectly), but let's hear it from you first… what would be your solution to this problem?
or
SPT + Inter VLAN Switching(not sure).
Every ethernet interface goes into this vlan, and routes points to the next hop(not interface). SPT should handle L2 connectivity issues.
Are the same than yours?
2. Spanning Tree, blocking the radio interface.
3. LACP, bundle both and use all the bandwidth.
so etherchannel, or udld. but udld needs additional configuration with errdisable stuff, that's why, imho, etherchannel is better :)
and yes, it's a very common case :)
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I was considering deleting your post, but decided to leave it as it is.
The boss is an idiot and should be educated or removed. The questioner's time would be best spent finding out why the boss has an irrational fear against the right tool for the job.
http://www.cisco.com/en/US/docs/switches/lan/catalyst2950/software/release/12.1_11_yj4/configuration/guide/swmstp.html#wp1039394
Has the OP looked at how the media converter is set up? Many media converters have a test mode where a down link status is not passed from one side to another. Once you take it out of test mode, it will pass status. Usually it's a small push button, or a switch.
Sean
Configure VLAN interface on both 3750, on on that VLAN use the smallest possible MAC address table timeout. Spanning tree will do the rest....
dan
Usually there are some dip switches you can flip that will allow the unit to pass line-protocol. Check the documentation or manufacturers FAQ section.
With the line-protocol issue fixed you just need to use static routes which include the interface syntax. Give the radio link a higher metric. Ethernet link drops, route gets removed and other link is used
I have the same network schema, but I have no problem using RIP. I'll to use RIP for automatic route change in case that one of them fails.
The problem is that I want application traffic to work on the main line and the rest of the traffic on radio.
Any idea how can i do that? QoS based on destination address?iZvyk
Please consider the following:
FWSM-6509 (Act) -> 3750E -> managed IPS -> 7206vxr-> ISP A
| | |
FWSM-6509 (Sty) -> 3750E -> managed IPS -> 7206vxr-> ISP B
With the externally managed IPS devices (bridged interfaces that don't forward BPDU's) between the border router and the perimeter switch-stack, links on the 3750E's stay up even if a border router fails / reloads for maintenance, etc (mush like the media converters in the original problem). I have come across many of the same solutions that others have presented here only to discard them as:
STP doesn't work since the IPS device discards BPDU's.
LACP is not supported on the 7206vxr (even though lacp is listed as a supported feature on 12.4(24)T2). Etherchannel works fine but if only one link fails
UDLD aggressive doesn't register the link loss
The IPS devices have multiple in/out interfaces so I had created cross-stack etherchannels between the 3750 switch stack and each 7206vxr, attempting for greater redundancy - it seems that single links to the 7206 routers would make fault detection much simpler. I would prefer not to run a dynamic routing protocol in this area of the network, but I will if it is the "best" solution.
Eagerly looking for the other 'in the meantime' solutions...
http://blog.ioshints.info/2007/09/static-routing-with-catalyst-3750-and.html