We've ran across both before when a layer3 switch is involved that was previously used for layer2 functions only - worked fine, but we did go back and remove the "ip default-gateway" statement...
Paul -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jon Lewis Sent: Saturday, January 12, 2008 11:25 AM To: [EMAIL PROTECTED] Cc: [email protected] Subject: Re: [c-nsp] problem of both "ip route 0.0.0.0" and "ip default-gateway" configured On Sat, 12 Jan 2008 [EMAIL PROTECTED] wrote: >> Someone mentioned that configuring both commands on the same router/switch >> causes trouble, i wonder if someone can help me understand why? >> >> 1) ip route 0.0.0.0 next-hop >> 2) ip default-gateway next-hop > > Why do you *want* to configure both? 1 is supposed to be used for an L3 > box (router), 2 is supposed to be used for an L2 box (switch). AFAIK, ip default-gateway is only used when IP routing is off/unsupported. It can be useful if a device ends up booting into boot IOS that doesn't support routing (like some of the older run from flash platforms during a software upgrade where you have to reboot from ROM, download new code to flash, and then boot the new code). I've got lots of gear with both a default route and an ip default-gateway and no problems. > If the interface in question is a broadcast medium (Ethernet), the router > doesn't know the next-hop address, resulting in a high rate of ARPs. This > has been dicussed on the list many times before, and the advice is simple: > Don't do it! It can work...but its very delicate and really pisses people off when someone with more clue is asked to take over management of the network. ---------------------------------------------------------------------- Jon Lewis | I route Senior Network Engineer | therefore you are Atlantic Net | _________ http://www.lewis.org/~jlewis/pgp for PGP public key_________ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.1/1220 - Release Date: 1/11/2008 6:09 PM _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
