Connecting a cisco 4908 to HP Procurve

Unanswered Question
Oct 18th, 2008

I have a cisco 4908 switch with 2 fiber gbics and 1 copper gbic. Actually I just added the copper gbic, because I want to connect an HP procurve 2810 48 port copper rj-45 Gigabit switch. The figer gbics were configured by a cisco guy and they have been working fine for years. I have never configured a layer3 cisco switch but have configured many catalyst 2950 switches. Through that experience I was able to get a link light on the port where I connected the HP procurve (its port 6 and the port was initially shutdown, but I enabled the port and the link light turned on). However I cant get through to my network from the HP Procurve.

I ran "show run" and tried to duplicate the configuration of one of the other fiber ports (port 7) to the newly installed copper gbic port (See the attached graphic). I added a sub interface port (6.1) and made the changes as they were set on port 7.1. However I still cant get through.

The ip address of the 4908 is 10.34.4.91.

The ip address I put on the HP procurve is 10.34.4.77. I added this ip address to port 6.1 becuase the ip address that is on port 7.1 is the ip address of the cisco 2950 that is connected to fiber gbic port 7. I figured that should be the same on port 6 and 6.1. Nevertheless, it didnt work.

Can anyone help me figure out what I'm missing. Thanks!!

Attachment: 
I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
Giuseppe Larosa Sat, 10/18/2008 - 12:26

Hello Danny,

you don't need to set ip addresses on each link

a multilayer switch can use L2 links to connect to other devices:

probably you need only one IP address under a logical interface that is named BVI1

Here the syntax is IRB like (integrated routing and bridging)

Check if the following is present:

int BVI1

ip address 10.34.4.91 255.255.255.0

no shut

the subifs 6.1 and 7.1 must be configured with

int g6/1.1

no ip addr

bridge-group 1

int g7/1.1

no ip addr

bridge-group 1

These must be on global configuration mode check if they are present:

bridge 1 bridge ip

bridge 1 route ip

bridge 1 protocol ieee

This should be a correct config.

Another option if IOS supports it is to use logical interface for Vlan

see

http://www.cisco.com/en/US/docs/switches/lan/catalyst4500/12.2/25sg/configuration/guide/l3_int.html#wp1029700

Hope to help

Giuseppe

wanman06621 Sat, 10/18/2008 - 12:38

Thanks for the info and the quick response. You mentioned BVi1. Can you explain the significance of int BVi1 and how I can check if it is present.

Also you mentioned global configurations

bridge 1 bridge ip

bridge 1 route ip

bridge 1 protocol ieee

How can I check if these are present?

Thanks Again.

Giuseppe Larosa Sat, 10/18/2008 - 12:47

Hello Danny,

to get this info you need to use

term len 0

show run

collect the output in a log file try to use a more powerful client telnet like putty for doing this: if you look in other threads the files are text files not screenshots !

in a telnet session to C4908 you need to be in enable mode.

hostname#

BVI1 is the logical L3 interface associated with bridge-group 1.

link for download of putty:

http://www.chiark.greenend.org.uk/~sgtatham/putty/

Hope to help

Giuseppe

wanman06621 Sun, 10/19/2008 - 09:44

I downloaded and used putty to telnet to the 4908. I ran show run and attached the log.

Also, I removed the ip address from g6.1 as you mentioned. I havent been able to find any reference to BVi1 in the show run output.

Any help is appreciated.

Attachment: 
Giuseppe Larosa Sun, 10/19/2008 - 12:43

Hello Danny,

I see there is

bridge 1 protocol ieee

I see something I think shouldn't work:

int g7.1

ip address 10.34.4.101 255.255.255.0

int gi8.1

ip address 10.34.4.91 255.255.255.0

In my experience these commands shouldn't even be accepted because these are overlapping ip addresses on Vlan subifs.

I've found an explanation for this:

one of the first lines is:

no ip routing

I would try to implement IRB in the correct way:

if you are not one of two ip addresses to telnet to c4908 do:

get a console access to C4908 and do the following:

conf t

int gi7.1

no ip address

int gi8.1

no ip address

exit

ip routing

bridge 1 bridge ip

bridge 1 route ip

int bvi1

ip address 10.34.4.91 255.255.255.0

no shut

the key parameter is no ip routing with this command the switch behaves like a L2 switch.

By using ip routing the behaviour becomes L3 switch.

Hope to help

Giuseppe

wanman06621 Sun, 10/19/2008 - 13:15

Thanks for the info, however on port 7 and port 8 I have a cisco 2950 switch. All those switches are working fine.

The problem I'm having is getting the HP Procurve (which is connected to port 6) to communicate with the rest of my network.

Are you saying that by making the changes you suggested, the HP Procurve will be able to communicate to the rest of my network? Also will my existing switches on port 7 and 8 continue to work properly?

Thanks Again.

Giuseppe Larosa Mon, 10/20/2008 - 01:07

Hello Danny,

I was suggesting what according to my experience is a working configuration.

However, I understand your point of view.

Let's not consider the problem of the general config.

You need to check the behaviour of the link between the two devices.

on C4908 with current config:

ethernet frames with vlan-id 1 are sent out with no Vlan tag: (native keyword)

you need to check on the HP procurve how the link is configured to understand if the two configurations are matching.

Config on ports 7 and 8 should still work with my suggested config but the problem with hp procurve could sit at layer 2 and so changing at layer3 can be not effective to solve.

Hope to help

Giuseppe

Actions

This Discussion