09-18-2006 03:17 AM - edited 03-03-2019 02:02 PM
Hello,
I have a point to multi-point Ethernet networdk on SDH backbone. The hub site needs to be working in primary-backup mode. But since the WAN interface is Ethernet, the line protocol will not go down if any remote site link fails and hence, the failover will not happen.
Is there any way to track multiple routes and then if one of them is not avilable via the primary link, the router selectively failover the traffic ONLY for that particular route onto the backup link?
Solved! Go to Solution.
09-18-2006 05:32 AM
Sorta got distracted by the HSRP discussion and didn't read you question closely.
HSRP does little good if the primary and the secondary are on the same router.
Running a routing protocol on both the primary and backup links is your best option. I assume you can't do that is the reason for the question.
It is possible to use policy based routing based on the track options also. If you are talking about a lot of subnets it could get to be a pain to configure.
http://www.cisco.com/en/US/tech/tk364/technologies_configuration_example09186a0080211f5c.shtml
09-18-2006 05:57 AM
I agree with Tim's point that HSRP is not the right answer for the issue described in the original post. But I come at it from a slightly different perspective. The original post described a point to multipoint environment and wants to fail over for a particular destination - but not all destinations - if that particular destination fails on the primary connection. But HSRP and track will fail the interface to the standby for ALL destinations if it fails for ANY destination.
I believe that we could give better answers if we understood the environment better. But given what we know now I agree with Tim that a dynamic routing protocol is likely to be a more satisfactory solution to the issue in the orignal post.
HTH
Rick
09-18-2006 03:33 AM
YES,
you can use the 'standby track ...' command in your hsrp group(s) to track multiple interfaces for their status.
(this would require multiple 'standby track' commands per hsrp group; this cannot be done in a single 'standby track' statement)
ie:
standby 1 ip 10.10.10.1
standby 1 priority 105
standby 1 preempt
standby 1 track vlan 987
standby 1 track vlan 985
if one of the interfaces becomes unavailable, HSRP can 'track' this and switch to the other route.
(replace vlan with an interface if thats what you need to track)
please see the following link for more HSRP tracking info:
http://www.cisco.com/en/US/tech/tk648/tk362/technologies_tech_note09186a0080094e8c.shtml
09-18-2006 04:03 AM
Thanks for this. I am testing this on Cisco 7206 NPE-G1 but here I donot see any option to track the vlan. Is there some IOS version from which this feature is available. The options that I have are:
SAR3.LAB(config-subif)#standby 99 track ?
<1-500> Tracked object number
Async Async interface
BVI Bridge-Group Virtual Interface
CDMA-Ix CDMA Ix interface
CTunnel CTunnel interface
Dialer Dialer interface
GigabitEthernet GigabitEthernet IEEE 802.3z
Lex Lex interface
Loopback Loopback interface
MFR Multilink Frame Relay bundle interface
Multilink Multilink-group interface
Port-channel Ethernet Channel of interfaces
Serial Serial
Tunnel Tunnel interface
Vif PGM Multicast Host interface
Virtual-PPP Virtual PPP interface
Virtual-TokenRing Virtual TokenRing
XTagATM Extended Tag ATM interface
09-18-2006 05:17 AM
They changed it
Cisco IOS Release 12.2(15)T and Later Releases
standby [group-number] track object-number [decrement priority-decrement]
no standby [group-number] track object-number [decrement priority-decrement]
Cisco IOS Release 12.2(13)T and Earlier Releases
standby [group-number] track interface-type interface-number [interface-priority]
no standby [group-number] track interface-type interface-number [interface-priority]
You need to build a track object which of can track a interface. But I suspect in your case tracking the ethernet interface will not do any good.
It would be nice if you could directly track existiance of a route in the routing table like BGP conditional advertisement does but I have not seen that option.
You can sorta do that by building a tunnel interface that has the destination as something that is learned dynamically. I think the tunnel will go down if it loses the route and you can track the tunnel. Of course you could build a real tunnel and use keepalives on it.
The other options if you have very new IOS is
http://www.cisco.com/en/US/products/sw/iosswrel/ps5207/products_feature_guide09186a00801d2d74.html
09-18-2006 05:32 AM
Sorta got distracted by the HSRP discussion and didn't read you question closely.
HSRP does little good if the primary and the secondary are on the same router.
Running a routing protocol on both the primary and backup links is your best option. I assume you can't do that is the reason for the question.
It is possible to use policy based routing based on the track options also. If you are talking about a lot of subnets it could get to be a pain to configure.
http://www.cisco.com/en/US/tech/tk364/technologies_configuration_example09186a0080211f5c.shtml
09-18-2006 05:57 AM
I agree with Tim's point that HSRP is not the right answer for the issue described in the original post. But I come at it from a slightly different perspective. The original post described a point to multipoint environment and wants to fail over for a particular destination - but not all destinations - if that particular destination fails on the primary connection. But HSRP and track will fail the interface to the standby for ALL destinations if it fails for ANY destination.
I believe that we could give better answers if we understood the environment better. But given what we know now I agree with Tim that a dynamic routing protocol is likely to be a more satisfactory solution to the issue in the orignal post.
HTH
Rick
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide