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I am not sure how to configure HSRP in my scenario: I have 2 distribution 2950 switches, each connected to two core 3560 switches.

Distribution switches work in VTP transparent mode and (for now) all access ports on Access switches are in VLAN 100.

The default gateway address is 192.168.1.1 for HSRP virtual IP address. I basically have two pairs of links, from each Distribution switch. Should I configure two separate HSRP groups for each switch connected to Core layer, let's say:

Group 1 Core 1 - Port 0/1 - IP 192.168.1.2 - priority 105 connected to Distribution 1 Core 2 - Port 0/1 - IP 192.168.1.3 - priority 100 connected to Distribution 1

Group 2 Core 1 - Port 0/2 - IP 192.168.1.4 - priority 105 connected to Distribution 2 Core 2 - Port 0/2 - IP 192.168.1.5 - priority 100 connected to Distribution 2

? Should they all have standby IP address set to 192.168.1.1??

UPDATE

Full topology

Where I need to set up HSRP for Distribution 1 & 2, based on that example I can handle the rest.

Would you suggest using SVIs?

  • Since your distribution switches are not L3 switches, I assume connections between distribuion and core are L2 links, not routing. Could you please confirm? If so, have you considered using SVIs for L3 interfaces in your core switches? If possible, please complete your question with a topology diagram showing connections between core switches, connections between distribution switches and connections between distribution and access switches. – Daniel Yuste Aroca Jun 7 '15 at 11:33
  • added the full topology, I do need SVIs, but I'm not sure how to configure it properly with HSRP in that topology. I need Core 1 to be active for both Distribution 1 & 2 and ideally, if link between Core 1 and Distribution 1 goes down, Distribution 1 start using Core 2 (but D2 still uses Core 1). – pzaj Jun 7 '15 at 12:00
  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could provide and accept your own answer. – Ron Maupin Aug 11 '17 at 17:12
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I would use SVIs for the L3 interfaces at core instead of assigning the IP configuration to physical ports.

This way, having VLAN 100 allowed in all links between Core1, Core2, Distribution1 and Distribution2 the Spanning Tree protocol will manage which of the available uplinks will be used to forward traffic between distribution and core.

A config sample for HSRP with SVI would be:

Core1

interface vlan 100 
  ip address 192.168.1.2 255.255.255.0
  standby version 2
  standby 100 ip 192.168.1.1
  standby 100 priority 105
  standby 100 preempt
!

Core2

interface vlan 100
  ip address 192.168.1.3 255.255.255.0
  standby version 2
  standby 100 ip 192.168.1.1
  standby 100 preempt
!

Should you need more information regarding the configuration options for HSRP in your 3560´s you can check the 3560 configuration guide for the software release you are using. For instace: http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3560/software/release/12-2_52_se/configuration/guide/3560scg/swhsrp.html

  • Thanks a lot, I think that will solve the "problem" :) also you're right, this solution is way more flexible! I believe I should create an SVI for each VLAN within my network and set HSRP for each one as an individual standby group? – pzaj Jun 7 '15 at 16:16
  • I also want RSTP to work here, will that affect the configuration by any chance? Should I set tracking for SVIs as well? Would you mind me contacting you any way, e.g. twitter, email? – pzaj Jun 7 '15 at 16:22
  • Default RSTP configuration would deal properly with the multiple links. If you are using high speed links and link aggretation you may want to use 802.1t 32-bit costs, that can be enabled with option spanning-tree pathcost method long. Regarding HSRP, just make sure STP root for a given vlan is the HSRP active switch for this VLAN in normal situation. For tracking, we would need to know how connections from core towards upstream networks are done. – Daniel Yuste Aroca Jun 7 '15 at 19:34
  • alright, so from what I understand, if I turn on RSTP and HSRP the way You've just shown it should properly work? So that if Core 1 (active, Root Bridge) goes down Core 2 takes the responsibilities of HSRP active and Root Bridge? :> What if, for example, Link between Core 1 and Distribution 1 goes down? Will all the traffic be sent through Distribution 2 or will Distribution 1 use the connection to Core 2? I didn't set up any path costs, I left them to be default as there's no need to load balance the traffic, I just need to make sure it will reach data center in case Core 1 goes down. – pzaj Jun 7 '15 at 20:31
  • In STP is working as expected with default costs, when link between Distribuition1 and Core1 goes down, distribution1 will use uplink to Core2 and traffic will go Distribution1 -> Core2 -> Core1, while Distribution2 will continue using its direct uplink towards Core1 – Daniel Yuste Aroca Jun 8 '15 at 19:20

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