HSRP first hop interface is unknown

[mahesh18]

Hi Everyone,

I am trying to config HSRP tracking ip route on Switch 3550A.

Switch 3550A and B are running HSRP on vlan 20.

Switch 3550A has next hop to Router.

Below is my config  on 3550A

track 11 ip route 172.31.3.0 255.255.255.0 metric threshold

threshold metric up 61 down 62

3550SMIA#sh run int vlan 20

Building configuration...

Current configuration : 257 bytes

!

interface Vlan20

ip address 192.168.20.1 255.255.255.0

ip ospf hello-interval 40

standby 1 ip 192.168.20.3

standby 1 priority 150

standby 1 preempt delay minimum 60

  standby 1 track 11 decrement 60

3550SMIA#sh track 11

Track 11

  IP route 172.31.3.0 255.255.255.0 metric threshold

  Metric threshold is Down (no route)

    1 change, last change 00:08:19

  Metric threshold down 62 up 61

  First-hop interface is unknown

  Tracked by:

    HSRP Vlan20 1

3550SMIA#sh ip route 172.31.3.0

Routing entry for 172.31.3.0/24

  Known via "ospf 1", distance 110, metric 300, type extern 2, forward metric 1

  Last update from 192.168.5.3 on FastEthernet0/11, 3w5d ago

  Routing Descriptor Blocks:

  * 192.168.5.3, from 4.4.4.4, 3w5d ago, via FastEthernet0/11

      Route metric is 300, traffic share count is 1

Need to know why it is showing  Metric threshold is down and first hop int is unknown?

Regards

MAhesh

[Peter Paluch]

Hi Mahesh,

This is quite strange. At first, it seems to me to be a bug of some sort... I wonder: if you created another track object, say, 12, and referred to the very same route 172.31..3.0/24, would it also say that the route is unreachable? I am trying to find out if the track object 11 is "stuck" for any reason.

Best regards,

Peter

[mahesh18]

Hi Peter,

I did not create any other track object that points to same route.

so you agree that my config is correct?

3550SMIA#                    sh track

Track 11

  IP route 172.31.3.0 255.255.255.0 metric threshold

  Metric threshold is Down (no route)

    1 change, last change 03:35:04

  Metric threshold down 62 up 61

  First-hop interface is unknown

  Tracked by:

    HSRP Vlan20 1

Regards

MAhesh

[Peter Paluch]

Hi Mahesh,

Yes, I agree that your configuration is correct. I would have done it quite in the same way. However, I actually want you to create another track object that refers to the same route I want to see if the other object complains about the same issue as your track object 11.

Best regards,

Peter

[mahesh18]

Hi Peter,

I created another track object as below

3550SMIA(config)#track 12  ip route 172.31.3.0 255.255.255.0 metric threshold

3550SMIA#sh track

Track 11

  IP route 172.31.3.0 255.255.255.0 metric threshold

  Metric threshold is Down (no route)

    1 change, last change 00:00:55

  Metric threshold down 255 up 254

  First-hop interface is unknown

  Tracked by:

    HSRP Vlan20 1

Track 12

  IP route 172.31.3.0 255.255.255.0 metric threshold

  Metric threshold is Down (no route)

    1 change, last change 00:00:13

  Metric threshold down 255 up 254

  First-hop interface is unknown

Seems it did not complain.

Seems as it is not seeing route in routing table even thogh route exists thats the reason it is taking the interface down right?

Regards

Mahesh

[Peter Paluch]

Hi Mahesh,

This is getting even stranger. I wonder - if you tried clear ip route * or clear ip ospf process to renew the contents of the routing table, would the track objects and their states change? Please note that these commands will cause temporary interruption in your traffic so do this only if there is no important traffic being routed right now, and allow for up to 10 seconds for the connectivity to recover.

If this does not help then I believe you should try upgrading the IOS, as this smells very strongly as an IOS bug.

Best regards,

Peter

[mahesh18]

Hi Peter,

I did clear ip ospf process still same thing.

Also the IOS which i have is latest what cisco has.

3550SMIA#                                       sh inventory

PID: WS-C3550-24PWR-SMI

3550SMIA# sh flash

Directory of flash:/

     2  -rwx     9707290  Mar 25 2010 16:37:50 -06:00  c3550-ipservicesk9-mz.122-44.SE6.bin

Seems nothing much more i can try now at this point.

Thanks for your help

Regards

Mahesh

[glen.grant · Accepted solution]

  Try adding this to your track statement and see what happens. Put it ahead of the entry of the route itself .

track 11 interface f0/11 ip routing

[mahesh18]

Hi Glen,

Here is what i did

3550SMIA#sh run | inc track

track 11 ip route 172.31.3.0 255.255.255.0 metric threshold

standby 1 track 11 decrement 60

3550SMIA#config t

Enter configuration commands, one per line.  End with CNTL/Z.

3550SMIA(config)#no track 11 ip route 172.31.3.0 255.255.255.0 metric threshold

3550SMIA(config)#track 11 interface f0/11 ip routing

3550SMIA(config-track)#track 11 ip route 172.31.3.0 255.255.255.0 metric threshold

% Cannot change tracked object 11 - delete old config first

3550SMIA(config)#end

Seems system does not allow to put the second track 11 command again.

Is this default behaviour?

3550SMIA#sh track

Track 11

  Interface FastEthernet0/11 ip routing

  IP routing is Up

    1 change, last change 00:00:34

  Tracked by:

    HSRP Vlan20 1

now the int vlan 20  is active for HSRP vlan 20.

sh standby shows

Vlan20 - Group 1

  State is Active

    14 state changes, last state change 00:02:29

  Virtual IP address is 192.168.20.3

  Active virtual MAC address is 0000.0c07.ac01

    Local virtual MAC address is 0000.0c07.ac01 (v1 default)

  Hello time 3 sec, hold time 10 sec

    Next hello sent in 0.588 secs

  Authentication MD5, key-chain "mahesh"

  Preemption enabled, delay min 60 secs

  Active router is local

  Standby router is 192.168.20.2, priority 100 (expires in 8.592 sec)

  Priority 150 (configured 150)

    Track object 11 state Up decrement 60

Need to undertsand what difference above command makes now?

Best reagrds

Mahesh

[mahesh18]

Many thanks Glen.

Regards

MAhesh