static route and eigrp two questions

[yongqiang.jin]

first:

I use static float route to use backup interface,and destination are two net: 21.0.0.0,22.0.0.0 but when master interface serial down ,only the net 21.0.0.0 next hop chage to backup interface and net 22.0.0.0 still use default next hop (the master interface,even it is down),why? it is so strange!

config is below:

interface Serial5/0

ip address 22.52.127.6 255.255.255.252

ip access-group 144 in

ip access-group 144 out

encapsulation ppp

!

ip route 21.52.64.0 255.255.224.0 22.52.124.25 80

ip route 21.52.64.0 255.255.255.0 21.52.127.5

ip route 22.52.64.0 255.255.224.0 22.52.124.25 80

ip route 22.52.64.0 255.255.255.0 21.52.127.5

#show ip interface brief

Serial5/0 22.52.127.6 YES NVRAM down down

#show ip route

S 21.52.64.0/19 [80/0] via 22.52.124.25

S 22.52.64.0/19 [1/0] via 21.52.124.5

#show version

IOS (tm) 7200 Software (C7200-JS-M), Version 12.1(20)E, EARLY DEPLOYMENT RELEASE

SOFTWARE (fc1)

The strange happened in all my wan interface! and I have another 7206 with different IOS at work online too,and even have the trouble!!!

second:same router and same config, i use eigrp too, but when i use no auto-summary config why still a summary address in route table???

#show running-config

router eigrp 1

network 21.0.0.0

network 22.0.0.0

network 23.0.0.0

no auto-summary

eigrp log-neighbor-changes

no eigrp log-neighbor-warnings

#show ip route

D 21.52.0.0/17 is a summary, 21:55:13, Null0

any suggest is thankful!!

DAVID

[Harold Ritter]

1)

It is not so strange. Your static route only specifies a next hop. As long as the next hop for that static route (in this case 21.52.127.5) is resolvable , either via a directly connected route or via any other route, the static route will remain in the routing table.

If you want to make sure that the static route is removed after the interface goes down, use the following syntax:

ip route 21.52.64.0 255.255.255.0 se5/0

ip route 22.52.64.0 255.255.255.0 se5/0

2) The summary installed by Eigrp in the routing table is not due to auto summarization (not on majornet boundary) but to manual summarization. Check your configuration for the following statement on one of the interfaces on this router:

ip summary-address eigrp 1 21.52.0.0 255.255.128.0 5

Hope this helps,