Unable to Configure HSRP on layer 3550 switch

[mahesh18]

Hi all,

I have home network where one router 2650 connects to ISP modem.

Router has direct connection to 3550 layer 3 switch .

3550  A  switch is connected to layer 2 switches.

I have got another 3550 B  switch and i need to establish redundant links between 3550  Switch A and B.

I  heard we can use HSRP between two 3550 switches.

If  someone can help me how i can configure 3550 B  switch to run HSRP .

I am posting my  config from 3550 A Switch.

Many thanks

Mahesh

[Nagaraja Thanthry]

Hello,

Is the link between the 2650 and 3550 a layer 3 link? Are the LAN hosts

point to 3550 as their default gateway? If not, then there is no point in

configuring HSRP. If you are pointing to 3550 as default gateway and you

have an extra interface on 2650 that connects to second 3550, then you can

configure HSRP.

Switch A:

interface vlan 1

ip address 10.1.1.2 255.255.255.0

standby 1 ip 10.1.1.1

standby 1 priority 254

standby 1 preempt

exit

Switch B:

interface vlan 1

ip address 10.1.1.3 255.255.255.0

standby 1 ip 10.1.1.1

standby 1 priority 100

standby 1 preempt

exit

Hope this helps.

Regards,

NT

[mahesh18]

Hi ,

Thanks for reply.

yes  the link between the 2650 and 3550 A  switch is layer 3 link.

Yes LAN hosts point to 3550 as their default gateway.

But my router has only  1 interface that goes to Switch A.No other interface is available

So you mean to say that  on Switch B  i can copy same config from Switch A ?

[Nagaraja Thanthry · Accepted solution]

Hello,

If you do not have a second link between the 2650 and 3550, then the HSRP

will provide redundancy at the LAN level i.e. if you have multiple vlans and

3550 is doing intervlan routing, then using HSRP, you can make sure that the

intervlan routing is unaffected as long as one of the switch is active.

However, if the switch to which the 2650 is connected (Switch A) goes down,

you will loose internet connectivity. You need to manually move the cable

from the switch A to Switch B. Other option would be for you to put a dumb

switch/hub between the 2650 and the switches. In that way, you can connect

both switches to same 2650 port.

As far as HSRP configuration is concerned, except the "standby priority"

rest of the configuration remains same on both switches.

Regards,

NT

[mahesh18]

Hi,

Thanks for the reply.

i have defined IP address range 192.168.1.x  for home network

For HSRP when i use

interface vlan 1

ip address 10.1.1.2 255.255.255.0   then do i have to define these ips  in dhcp pool also?

mahesh

[mahesh18]

Hi all,

I have 3550 A  switch and its config is attached.

Now i got 3550 B switch and i need hsrp on my Lan.

This is what i did

1> i copy all the config from 3550 A  switch to new switch 3550 B.

2>connect  int gi0/1  which is fibre link from 3550 A  to 35550 B   on port gi0/1.

3> when i did that then on 3550 B  switch i get this log

*Feb 28 17:31:42.720 MST: %SYS-5-CONFIG_I: Configured from console by console
*Feb 28 17:31:45.292 MST: %LINEPROTO-5-UPDOWN: Line protocol on Interface Gigabi
tEthernet0/1, changed state to up
*Feb 28 17:32:25.757 MST: %LINEPROTO-5-UPDOWN: Line protocol on Interface Gigabi
tEthernet0/1, changed state to down
*Feb 28 17:32:28.777 MST: %LINEPROTO-5-UPDOWN: Line protocol on Interface Gigabi
tEthernet0/1, changed state to up
*Feb 28 17:32:28.793 MST: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan10
, changed state to up
*Feb 28 17:32:28.793 MST: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan20
, changed state to up
*Feb 28 17:32:28.797 MST: %IP-4-DUPADDR: Duplicate address 192.168.10.1 on Vlan1
0, sourced by 000d.28bc.fd80
*Feb 28 17:32:28.797 MST: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan30
, changed state to up
*Feb 28 17:32:59.281 MST: %IP-4-DUPADDR: Duplicate address 192.168.10.1 on Vlan1
0, sourced by 000d.28bc.fd80
*Feb 28 17:33:29.298 MST: %IP-4-DUPADDR: Duplicate address 192.168.10.1 on Vlan1
0, sourced by 000d.28bc.fd80
*Feb 28 17:33:59.299 MST: %IP-4-DUPADDR: Duplicate address 192.168.30.1 on Vlan3
0, sourced by 000d.28bc.fd80
*Feb 28 17:34:29.300 MST: %IP-4-DUPADDR: Duplicate address 192.168.30.1 on Vlan3
0, sourced by 000d.28bc.fd80
*Feb 28 17:34:59.300 MST: %IP-4-DUPADDR: Duplicate address 192.168.30.1 on Vlan3
0, sourced by 000d.28bc.fd80
*Feb 28 17:35:01.236 MST: %SYS-5-CONFIG_I: Configured from console by mintoo on
vty0 (192.168.10.1)
*Feb 28 17:35:29.309 MST: %IP-4-DUPADDR: Duplicate address 192.168.30.1 on Vlan3
0, sourced by 000d.28bc.fd80
*Feb 28 17:35:59.310 MST: %IP-4-DUPADDR: Duplicate address 192.168.30.1 on Vlan3
0, sourced by 000d.28bc.fd80
*Feb 28 17:36:10.174 MST: %SYS-5-CONFIG_I: Configured from console by console
*Feb 28 17:36:29.319 MST: %IP-4-DUPADDR: Duplicate address 192.168.30.1 on Vlan3
0, sourced by 000d.28bc.fd80
*Feb 28 17:36:57.115 MST: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan10
, changed state to down
*Feb 28 17:36:57.119 MST: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan20
, changed state to down
*Feb 28 17:36:57.119 MST: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan30
, changed state to down
*Feb 28 17:36:57.739 MST: %SYS-5-CONFIG_I: Configured from console by console
*Feb 28 17:36:58.115 MST: %LIN

Also on 3550 A switch log shows

  6 12:27:35.563 MST: %IP-4-DUPADDR: Duplicate address 192.168.10.1 on Vlan10                                                                                                                               , sourced by 0009.e8a2.0080

Oct  6 12:28:06.052 MST: %IP-4-DUPADDR: Duplicate address 192.168.10.1 on Vlan10                                                                                                                               , sourced by 0009.e8a2.0080
Oct  6 12:28:36.337 MST: %IP-4-DUPADDR: Duplicate address 192.168.10.1 on Vlan10                                                                                                                               , sourced by 0009.e8a2.0080
Oct  6 12:28:46.261 MST: %CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on F                                                                                                                               astEthernet0/8 (not half duplex), with 2950T FastEthernet0/8 (half duplex).
Oct  6 12:29:06.337 MST: %IP-4-DUPADDR: Duplicate address 192.168.20.1 on Vlan20                                                                                                                               , sourced by 0009.e8a2.0080
Oct  6 12:29:36.338 MST: %IP-4-DUPADDR: Duplicate address 192.168.30.1 on Vlan30                                                                                                                               , sourced by 0009.e8a2.0080
Oct  6 12:29:46.266 MST: %CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on F                                                                                                                               astEthernet0/8 (not half duplex), with 2950T FastEthernet0/8 (half duplex).
Oct  6 12:30:06.339 MST: %IP-4-DUPADDR: Duplicate address 192.168.30.1 on Vlan30                                                                                                                               , sourced by 0009.e8a2.0080
Oct  6 12:30:36.468 MST: %IP-4-DUPADDR: Duplicate address 192.168.20.1 on Vlan20                                                                                                                               , sourced by 0009.e8a2.0080
(half duplex).
Oct  6 12:30:59.212 MST: %SYS-5-CONFIG_I: Configured from console by mintoo on v                                                                                                                               ty0 (192.168.5.1)
Oct  6 12:31:06.468 MST: %IP-4-DUPADDR: Duplicate address 192.168.20.1 on Vlan20                                                                                                                               , sourced by 0009.e8a2.0080
Oct  6 12:31:36.469 MST: %IP-4-DUPADDR: Duplicate address 192.168.20.1 on Vlan20

[mahesh18]

Also on 3550 A  switch i config

Switch A:

interface vlan 1

ip address 10.1.1.2 255.255.255.0

standby 1 ip 10.1.1.1

standby 1 priority 254

standby 1 preempt

exit

Switch B:

interface vlan 1

ip address 10.1.1.3 255.255.255.0

standby 1 ip 10.1.1.1

standby 1 priority 100

standby 1 preempt

[mahesh18]

Hi all

i Just attached the config from Switch B  whose hostname is Layer 3 switch.