Wired Intelligent Edge

hi there,

I facing strange problem. I have 2 Hp5406 core switches. I have dhcp server connected on core1 in vlan 132 and providing ip to ip-phones in the same vlan. It has been working fine, but all of the sudden phones stopped getting ip address from dhcp server.

Now while troubleshooting, i realised there is a problem with core1 switch. To test that, i made one testing vlan777 and allocated two port B9-B10 as untagged. I connected dhcp server into port-b9 and my laptop on B-10 but no ip address.

To make sure, if it is not the problem of DHCP server, i created vlan-777 on Core-2 switch and allocated B9-B1 ports. And Bingo......my dhcp server provide ip to my laptop without any problem.

Now i have no idea, why it is working on core-2, but not on core-1.

Find attached show tech all for core1 & core2 switch......i thought of restarting the core switch to see if it solve the problem but i could not get down time from client.

let me tell you, with static ip address on my laptop, i can ping to DHCP server from any part of the network inside vlan-132.

Appriciate if someone can help on this.

Attachment(s)

core1-showtech.txt   703 B 1 version

core2-showtech.txt   703 B 1 version

You do not appear to have any untagged ports on your vlan 132 in your core 1 device but you have 2 untagged in your core 2 device. You need to have untagged ports to allow for device access on that network. Also, it appears that you have made changes to the config per your report about unsaved changes. I am sure you are aware that if you reboot, you will lose any changes if you do nto save them. I hope this helps.

Yes, there is no untag port for vlan 132. Whereas my dhcp-server was connected to server switch, which i did not discussed in last port.

However, to test whether dhcp is working on core1 or not. I connected dhcp server inside isolated vlan-777.

When i connected dhcp-server on core1 port-b9 and laptop on b10........it did not work.

however, when i connected dhcp-server on CORE-2 port b9 and laptop B10, it works fine.

That is how i realised that probably some thing is wrong with core1 switch, which is not passing dhcp request.

let me tell you this vlan-777 is isolated vlan on core1 and core2,  i have not even tagged the trk1 which connects core1 and core2.

I think, something wrong with core1.

Could you please look into ARP and SHOW INTERFACE........probably it will give some idea........thanks for reply.

Are you sure it was 

laptop - b9

server - b10

?

I ask, because your port b10 on Core2 is tagged in VLAN132.

I can't quite see how this would make a difference (the laptop should be sending the request on VLAN1 and the DHCP server shouldn't be caring about the tagged VLAN it will be seeing traffic coming in on)...but still, get rid of the tagged VLAN on core2 b10 just to make sure you are comparing two identical configs.

The thing that makes me think this is worth looking into is the fact that whatever you have patched to b10 gave a PVID mismatch error which makes me think somebody's interface is configured funny.