Recently we've run into a couple of situations where our routing tables are mysteriously being altered. x.x.x.# represents a unique static route. y.y.y.1 represents the proper gateway for the eth3 interface. z.z.z.1 represents the proper gateway for the eth0 interface. The z.z.z.1 gateway is the default route for the system Normally, the routing table should look like this: # netstat -nr Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface x.x.x.101 y.y.y.1 255.255.255.255 UGH 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.224 UG 0 0 0 eth3 x.x.x.32 y.y.y.1 255.255.255.224 UG 0 0 0 eth3 x.x.x.96 y.y.y.1 255.255.255.224 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.224 UG 0 0 0 eth3 x.x.x.64 y.y.y.1 255.255.255.224 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 0.0.0.0 255.255.255.0 U 0 0 0 eth3 x.x.x.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 0.0.0.0 z.z.z.1 0.0.0.0 UG 0 0 0 eth0 At some point in the middle of doing an up2date on the server, the routing table becomes: # netstat -nr Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface x.x.x.101 y.y.y.1 255.255.255.255 UGH 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.224 UG 0 0 0 eth3 x.x.x.32 y.y.y.1 255.255.255.224 UG 0 0 0 eth3 x.x.x.96 y.y.y.1 255.255.255.224 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.224 UG 0 0 0 eth3 x.x.x.64 y.y.y.1 255.255.255.224 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 0.0.0.0 255.255.255.0 U 0 0 0 eth3 x.x.x.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 x.x.x.0 y.y.y.1 255.255.255.0 UG 0 0 0 eth3 0.0.0.0 y.y.y.2 0.0.0.0 UG 0 0 0 eth3 0.0.0.0 y.y.y.3 0.0.0.0 UG 0 0 0 eth3 0.0.0.0 z.z.z.3 0.0.0.0 UG 0 0 0 eth0 0.0.0.0 z.z.z.2 0.0.0.0 UG 0 0 0 eth0 0.0.0.0 z.z.z.1 0.0.0.0 UG 0 0 0 eth0 And as a result, the up2date fails and the networking services need to be restarted (service network restart). This results in the routing table being: 0.0.0.0 z.z.z.1 0.0.0.0 UG 0 0 0 eth0 The additional static routes are added by starting up our "backup-route" script. The .2 and .3 gateways are the physical routers, the .1 is a virtual. In talking with my networking folks, they said the routers are configured to do IRDP and that sometimes this might happen if the systems are configured for DHCP. However, these are _not_ configured to do DHCP. Any ideas? Has anyone seen this before? I've seen this on both physical hardware as well as VMware virtual machines. Thanks, Maarten Broekman Fidelity | Investment Management Technology Enterprise Platform Services Office: (617) 563-9756 Cell: (617) 590-8005 Email: maarten.broekman@xxxxxxx -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
