IP Port Unreachable - C5K responds to Client SQL ANY request

johnathanmoor · ‎01-06-2004

Got a SQL client based application, sends out an all network broadcast (SQL ANY udp 1498). Assuming no reply, the client will then unicast to the specific server. If an 'ICMP unreachable' is received the client will stop any further connection attempts.

We have the management interfaces of 2 cat5000 in the same vlan as the SQL client issuing the all network SQL ANY udp broadcast. These switches are responding to the broadcast as expected, but will not be listening to udp port 1498 and respond with and ICMP port unreachable, as expected and cause the client to stop any further SQL connection attempts.

Set ip unreachable disable on the catalysts what would you expect?

Cheers, John.

skarundi · ‎01-06-2004

you are right john. The "set ip unreachable" command is used only Catalyst fddi modules. I guess its one of those legacy commands that was not removed in later releases that do not support fddi modules.

Put the SQL servers and switch sc0 interfaces on different vlans. I don't know of any way to stop the switch from sending an icmp unreachable.

Here the URL describing the proper use of the command

http://www.cisco.com/en/US/products/hw/switches/ps679/products_configuration_guide_chapter09186a008007eee2.html#1020185

johnathanmoor · ‎01-07-2004

many thanks, moving the sc0 into a different vlan was exactly what I did :) Strangely enough we do have some C6K on the same VLAN that are not responding to the all network broadcast, hmmm. The CAT5K's are catos 4.5(4) and the CAT6K's are 6.3(7).