we opened a maintinance

Integration Support · ‎11-24-2016

we have two cisco routers , one is 1941 and 1841

they're both connecte dto BB switch

yesterday we disconnected LAN interface Gi0/1 on the active router (1941) and there was no failover .

please advise why failover didn't happened

here is my config:

1941 router:

interface GigabitEthernet0/1
description to LAN
ip address 172.16.55.2 255.255.255.248
ip helper-address x.x.x.3
ip helper-address x.x.x.8
ip flow ingress
ip flow egress
standby 0 ip 172.16.55.1
standby 0 priority 120
standby 0 preempt
standby 0 track 1 decrement 50
load-interval 30
duplex auto
speed auto
hold-queue 8000 in
hold-queue 8000 out
end

#sh standby
GigabitEthernet0/1 - Group 0
State is Active
    25 state changes, last state change 2d23h
Virtual IP address is 172.16.55.1
Active virtual MAC address is 0000.xxxx.ac00
    Local virtual MAC address is 0000.xxxx.ac00 (v1 default)
Hello time 3 sec, hold time 10 sec
    Next hello sent in 1.472 secs
Preemption enabled
Active router is local
Standby router is 172.16.55.3, priority 110 (expires in 9.216 sec)
Priority 120 (configured 120)
    Track object 1 state Up decrement 50
Group name is "hsrp-Gi0/1-0" (default)

1841 router:

#sh run int FastEthernet0/1

interface FastEthernet0/1
description #To Lan#
ip address 172.16.55.3 255.255.255.248
ip helper-address x.x.x.3
ip helper-address x.x.x.8
ip flow ingress
ip flow egress
duplex auto
speed auto
standby 0 ip 172.16.55.1
standby 0 priority 110
standby 0 preempt
standby 0 track 1 decrement 10
end

#sh standby
FastEthernet0/1 - Group 0
State is Standby
    25 state changes, last state change 2d23h
Virtual IP address is 172.16.55.1
Active virtual MAC address is 0000.xxxx.ac00
    Local virtual MAC address is 0000.xxxx.ac00 (v1 default)
Hello time 3 sec, hold time 10 sec
    Next hello sent in 2.740 secs
Preemption enabled
Active router is 172.16.55.2, priority 120 (expires in 7.408 sec)
Standby router is local
Priority 110 (configured 110)
    Track object 1 state Up decrement 10
Group name is "hsrp-Fa0/1-0" (default)

Mark Malone · ‎11-24-2016

Hi

Your hsrp is configured correctly and shows there was a state change 2 days ago which would say that it works ok , did you get any logs when you pulled the link on the router or switch connected ? did you check the STP status of the g0/1 on the switch connection to the router when you pulled the link

Integration Support · ‎11-24-2016

On the HP backbone switch i can learn all three ip addresses:

172.16.55.1      00xxxx-07ac00     dynamic B1
172.16.55.2      bcxxxx-487bc1     dynamic B1
172.16.55.3      00xxxx-f903c1     dynamic D24

And on STP status both interfaces connected to both routers are in Forwarding state:

B1 100/1000T | 20000 128 Forwarding | 2cxxxx-344e00 2 Yes Yes
D24 100/1000T | 200000 128 Forwarding | 2cxxxx-344e00 2 Yes Yes

Mark Malone · ‎11-24-2016

Yes that's the issue its all reset now back working and showing as correct so finding out what happened will be very difficult to know as it was a real time issue , you need to pull the link again and debug the HSRP to see what exactly is happening if its not working still on failover

Integration Support · ‎11-24-2016

can the clock on both router couse a problem to HSRP not to work if both clocks are not same ?

Mark Malone · ‎11-25-2016

No absolutely not but it won't help your logging having times incorrect , HSRP is an independent protocol it runs without a requirement from any other service including clocks , when HSRP fails in failover 9 times out of 10 its a layer 1 or 2 issue

Integration Support · ‎12-01-2016

today we tested again the HSRP and the HSRP worked fine . but the network still was down . the was no ping to google

we noticed that when we disconnected the cable from Gi0/1 the standby router bacame active

in traceroute from the PC we reached until the active router but it stop there . the next hop hirarchy layer is two cisco router connected to each other via EIGRP.

which i think that the next hop router is still forwarding the LAN network to the other one !

why this is happening ?

I attached photo almost explain what is happening ..

Mark Malone · ‎12-01-2016

Is there a reason your using EIGRP between the 2 routers if HSRP is acting as the failover mechanism between the 2 routers ?

Its difficult to say why without seeing your routing setup as now the problem is layer 3 rather than the HSRP , if you shut the EIGRP link both sides does it work ok or try set a very high EIGRP delay so its not a preferred path

Integration Support · ‎12-02-2016

no its not like that

as you can see in the topology i attached before , the two cisco routers acting in HSRP are in the distribution layer . in the core layer we have another two cisco routers acting in EIGRP two share routes between eath other .

chrihussey · ‎12-02-2016

It is a little confusing looking at your drawing.

Is it the 10.10.66.0/24 subnet that loses connectivity to the Internet? If so, are both routers advertising it in their EIGRP? (more importantly the 1841 when active)

Integration Support · ‎12-15-2016

we opened a maintinance windows today morning and we resolved the with one of our cisco experts

just wanted to share with you guys which configurations we needed in order to fix the problem :

track 2 interface GigabitEthernet0/1 line-protocol
standby 0 track 1 decrement 50

ip route 10.10.xx.0 255.255.255.0 172.16.55.6 track 2
(xx= all our LAN networks)

router eigrp 1
network 172.16.206.0 0.0.0.7
redistribute static
redistribute connected
passive-interface GigabitEthernet0/1

HSRP not working