Network Issue

tstrip007

I am not an networking expert by any means and I am having an issue thats seems to be zeroed in on hosts on a particular vlan. About every hour they will lose network connection. I am using dell 6248 switches stacked. When I flush the arp cache or remove all dynamic entries it comes back for them temporarily. Ive done a port mirroring sesh on a port that belongs to one of the pc's that continues to have the issue but dont know what to look for. Any advice? Ty in advance.

Edit: Ive done AV and malware scans on all pc's. All good there.

lsud00d

I'm not sure on the network side of things but are the PC's getting info via DHCP?

Since you have mirroring enabled, sniff on UDP 67 & 68 to watch the communications between client and server.

Is DHCP relay properly configured on the Dell switch (if client/server are different subnets)?

What is being used for DHCP? What are the lease settings?

it_consultant

Can we get a running config of the dell stack? You can edit out IP's and passwords.

tstrip007

Thanks for the responses. Things have settled but it's because I have slowly moved these 9 users off the vlan one by one. We have an 03 domain controller where DHCP is setup. We have the hosts setup on this subnet for a one day lease. I did notice with one user that they kept getting an ip conflict message and when I rebooted or reenabled the nic, a new ip would not assign. Ended up throwing a static on it. Working on the running config it_consultant. Thanks

it_consultant

Sounds like you need to configure the DHCP helper address in the Dell stack for that VLAN.

pumpkin12345678

lsud00d wow you spotted a resolution straight away