HSRP problem

mpabilona · ‎04-04-2005

We are frequently experiencing problem in our HSRP implementation. Please refer the logs below. Our workaround is to clear the arp cache and it goes normal temporary. Is it advicable to set the HSRP hello interval in higher than the default? What are the possible cause of the problem? Please present your suggestions to permanently solve our problem. Thank you.

Router1: Active Router

LO : 202.x.x.1

Port-Channel1

member0: FastEthernet4/0/1

member1: FastEthernet4/0/0

Port-Channel2

member0: FastEthernet0/0/1

member1: FastEthernet0/0/0

FastEthernet4/1/0

Router2: Standby Router

LO : 202.x.x.2

Port-Channel1

member0: FastEthernet4/0/0

member1: FastEthernet4/0/1

Port-Channel2

member0: FastEthernet1/0/0

member1: FastEthernet1/0/1

FastEthernet4/1/0

Router1:

Apr 4 15:11:25.596 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 2 state Standby -> Active

Apr 4 15:11:25.624 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 11 state Standby -> Active

Apr 4 15:11:25.640 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 6 state Standby -> Active

Apr 4 15:11:25.656 PHT: %HSRP-6-STATECHANGE: Port-channel1 Grp 9 state Standby -> Active

Apr 4 15:11:25.704 PHT: %HSRP-6-STATECHANGE: Port-channel1 Grp 3 state Standby -> Active

Apr 4 15:11:25.752 PHT: %HSRP-6-STATECHANGE: Port-channel1 Grp 9 state Active -> Speak

Apr 4 15:11:25.796 PHT: %HSRP-6-STATECHANGE: Port-channel1 Grp 3 state Active -> Speak

Apr 4 15:11:26.640 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 2 state Active -> Speak

Apr 4 15:11:26.672 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 11 state Active -> Speak

Apr 4 15:11:26.700 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 6 state Active -> Speak

Apr 4 15:11:36.912 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 2 state Standby -> Active

Router2 LOGS:

Apr 4 15:11:24.592 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 5 state Standby -> Active

Apr 4 15:11:24.592 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 10 state Standby -> Active

Apr 4 15:11:24.592 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 1 state Standby -> Active

Apr 4 15:11:24.596 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 7 state Standby -> Active

Apr 4 15:11:24.616 PHT: %HSRP-6-STATECHANGE: Port-channel1 Grp 8 state Standby -> Active

Apr 4 15:11:24.620 PHT: %HSRP-6-STATECHANGE: Port-channel1 Grp 4 state Standby -> Active

Apr 4 15:11:25.592 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 5 state Active -> Speak

Apr 4 15:11:25.596 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 10 state Active -> Speak

Apr 4 15:11:25.596 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 1 state Active -> Speak

Apr 4 15:11:25.596 PHT: %HSRP-6-STATECHANGE: Port-channel1 Grp 8 state Active -> Speak

Apr 4 15:11:25.600 PHT: %HSRP-6-STATECHANGE: Port-channel1 Grp 4 state Active -> Speak

Apr 4 15:11:25.604 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 7 state Active -> Speak

Apr 4 15:11:56.296 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 5 state Standby -> Active

Apr 4 15:11:56.296 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 10 state Standby -> Active

Apr 4 15:11:56.300 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 1 state Standby -> Active

Apr 4 15:11:56.300 PHT: %HSRP-6-STATECHANGE: FastEthernet4/1/0 Grp 7 state Standby -> Active

Georg Pauwen · ‎04-04-2005

Hello,

rather than increasing the timeout, which might actually help, I would check first if there is excessive traffic on the network, or if there are physical problems. Can you post the output of 'debug standby' ?

Regards,

GP

ankurbhasin · ‎04-05-2005

Hi,

The only reason both are becoming active is because hello packets are getting lost somewhere in the middle.

And if it is not a bug it is mostly the physical layer problem when the hello packets are coming from active router to standby router could be due to congestion it is getting lost in middle.

The best troubleshootng procedure will be to hard set speed and duplex settings between your routers and switches to which both your HSRP routers are connected. I hope that should take care of the problem if by anychance you are not hitting some HSRP bugs.

HTH

Ankur

mpabilona · ‎04-05-2005

Ankur,

many thanks =)

The FastEthernet connection between the two HSRP routers through our switch was set to 100mb/s and full-duplex. The statistics below are the interface of the standby router that connects to the active router. We observed an amount of Input queue drops/flush and increasing broadcasts traffic, does it affect the communication ,via hello protocol,of the two routers ?

Router2#show interface FastEthernet4/1/0

FastEthernet4/1/0 is up, line protocol is up

Hardware is cyBus FastEthernet Interface, address is 000d.6574.3688 (bia 000d.6574.3688)

Description: HSRP 2

Internet address is 202.x.x.x/25

MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,

reliability 255/255, txload 31/255, rxload 47/255

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

Full-duplex, 100Mb/s, 100BaseTX/FX

ARP type: ARPA, ARP Timeout 04:00:00

Last input 00:00:00, output 00:00:00, output hang never

Last clearing of "show interface" counters 01:43:20

Input queue: 0/75/676/3658 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 18567000 bits/sec, 5027 packets/sec

5 minute output rate 12163000 bits/sec, 4332 packets/sec

30951863 packets input, 1239998521 bytes, 0 no buffer

Received 73277 broadcasts, 0 runts, 0 giants, 21 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored

0 watchdog

0 input packets with dribble condition detected

24730230 packets output, 87932666 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

0 babbles, 0 late collision, 0 deferred

0 lost carrier, 0 no carrier

0 output buffer failures, 0 output buffers swapped out

mpabilona · ‎04-05-2005

GP,

From our standby router, we received the following log messages, does it causes failure to detect the hello message from the router1 (active) and resulted to change the states of our standby router to active?

Standby Router logs:

Apr 4 15:12:11.716 PHT: %LDP-5-NBRCHG: LDP Neighbor 202.x.x.1:0 is DOWN

Thanks.

Georg Pauwen · ‎04-05-2005

Hello,

indeed the failure of receib=ving the hello packet causes the state change.

As previously suggested by Arthur and me, I would check for congestion or physical problems on your network. Check the output of 'show interfaces' for any increased error counter especially FCS and CRC.

Regards,

GP