Vlan redundency

[Carpua]

Hi all

i've got two CW6509 cisco series. the problem is the vlan 125. when i plug devices on the 2nd core they drop packets but i plug the into core 1 they dont drop. but any other vlan works fine on the 2nd core
core 1
interface Vlan250
description Server VLAN
ip address 10.54.125.2 255.255.255.0
ip helper-address 10.54.125.222
standby 125 ip 10.54.125.1
standby 125 priority 200
end
core 2
interface Vlan250
description Link to Server Switches
ip address 10.54.125.3 255.255.255.0
ip helper-address 10.54.125.1
standby 125 ip 10.54.125.1
standby 125 priority 150
standby 125 preempt
end

is there anything wrong with the above config

 

[baddos]

Well your helper addresses are different, Not sure if thats intential or not. Can you ping both 10.54.125.2 and 10.54.125.3 from another host somewhere?

 

[Carpua]

yes i can ping both IPs but when the end device is plugged on 10.54.125.3 it drops parkets but on 10.54.125.2 it works fine,Can the IP address helper cause that? the other vlans that are working have the same ip helper
e,g
core 1
interface Vlan122
ip address 10.54.122.2 255.255.255.0
ip helper-address 10.54.223.2
ip helper-address 10.54.125.222
standby 122 ip 10.54.122.1
standby 122 priority 150
standby 122 preempt

Core 2
interface Vlan122
ip address 10.64.122.3 255.255.255.0
ip helper-address 10.54.223.1
ip helper-address 10.54.125.222
standby 122 ip 10.54.122.1
standby 122 priority 200
standby 122 preempt

10.54.125.222 is the DNS
and 10.54.223.1/2 are both switches

 

[VinceWhirlwind]

What is it you think your IP helper addresses are actually doing for you?
IP helper addresses don't drop unicast IP packets.

What is an "ipconfig" from a host that is working fine?
What is an "ipconfig" from a host that is having problems?

Can the problem host ping its default gateway?
Can the problem host ping another host on a different subnet?

Identify the network path your problem host is using to get to its destination and do a "show interface" on each switch interface along that path looking for errors.

 

[Carpua]

hi VinceWhirlwind

if you looked at my first you will see that i said im only having problems with end host on the 10.54.125.0 subnet and they drop packets when plugged into the other switch. and yes they can ping the gateway and other subnet but they drop parkets and the reply is extremely slow.what i'm trying to find out is that is there anything wrong with the config for vlan 125.

 

[unclerico]

1) your DHCP server is in the same broadcast domain as the clients in your vlan250 so you should not need any helper configuration for that SVI
2) your helper address on vlan250 is the same as the VIP for your HSRP config on core2

 

[VinceWhirlwind]

Carpua, You've answered 2 of my 6 questions.
My questions are intended to direct you on your troubleshooting path.
As hinted by your respondents, your IP helper config on that VLAN is rubbish. This is why I'm suggesting you investigate what you think it should be doing. Answering that question will allow you to fix it.
However, if your hosts are successfully getting an IP address on their subnets, then the misconfiguration of your IP helper address is a red herring anyway.