2510 strange error

[ignasp]

Hello,

we have 2510-24 with optical adapter and 2 PC's. 2510-48 as main switches and various other HP switches connected to them in our network.

All of them are not configured, vlan's are not tagged, we just added password to out of the box config.

Our Windows Server (NAT, DHCP, DNS, AD) is connected to main 2510.

All of the computers that are in the network and use internal IPs are connected to those two 2510-48 and successive switches.

And this weird problem keeps appearing every 3-5 days since about 1 month ago.

DHCP was disabled as we used preset IPs in our client computers but all of them suddenly started showing IP conflicts, though computers with external IPs were working correctly.

So we set up DHCP to provide IPs for specific MAC addresses. It was OK for a few days but then the IP conflicts emerged again.

The only way to fix it is to reset that main 2510-24 switch. But it only helps for a few days.

Maybe someone can advise something?

[Fred_Mancen_1]

It seems that the switches are with its VLAN Interfaces 1 (default VLAN) with DHCP enabled. Did you already tried to disable the DHCP in the VLAN interface on the switches?

Regards

[Richard Litchfield]

The problem definition is still a bit loose. You will need to define exactly what and how many IPs have a problem, and track down the culprits. Make sure you have conflict resolution enabled in your DHCP server (so it tests before assigning a new IP address).

Commands from the switch CLI that may be useful:

show arp
show mac-address

[paulgear]

Richard is right. You need to be more specific about your problem definition.

As a general rule, if you have to reboot a managed switch more than once every year or two, either you have faulty hardware (which seems unlikely in this case), or you're doing something wrong.

Next time you get an IP address conflict, take the time to track down which MAC addresses are using the IP (by using 'show arp' on the switch and comparing this with the ARP tables on your workstations), then use the 'show mac-address' table on the switch to work out which port the offending system is on.

Static IP addressing is a recipe for conflicts. Take the time to get your entire network changed over to DHCP.

[ignasp]

No I did not, I'll try then.

[ignasp]

DHCP is misbehaving again.

Arp table is empty on main 2510-24, when connected with telnet to both 2510-48, arp table only shows internal ip of 2510-24 (10.0.0.6).

Mac address table lists all computers connected...

I'll just try tagging all vlans.