DNS Issue with VLAN's

I have a client with multiple VLAN's.

Basically VLAN 1 is where all the servers and switches reside and they are statically set.

All other workstations are set to their departmental VLAN's.

However, when setting up a new computer on a connection that is on VLAN 1 prior to either moving that port to a different VLAN or statically assigning an IP address, it will not resolve by name and NSLookup reports unknown server.

There is a DHCP pool for the VLAN 1 subnet, and the computer will get an ip address from that pool, and create a reverse lookup.
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abustraanConnect With a Mentor Author Commented:
I found out through further testing and suggestions on another board that this issue was caused by a bad arp table.

I went into the server, removed the arp entry for the problem computer, on the problem computer I deleted the arp table and everything worked immediately.

Thanks for the time.
Radhakrishnan RSenior Technical LeadCommented:

The DHCP pool on VLAN1 has any DNS server added? usually the client machines pick the DNS address from appropriate scope options where the DNS server added.

Unknown server usually comes when there are no A records for the particular server. I hope it's added.
abustraanAuthor Commented:
Thanks for the prompt response. Yes there's an (A) record for the DNS Server.

In addition there is a DHCP Pool for the VLAN 1 Subnet and it will issue an IP address to the workstation, it just won't resolve Hostnames to their IP Addresses.

As an added test, I just tried a Windows XP SP3 computer and I have the same results. If I use Vlan 1 no name resolution, if I use VLan 2 it resolves just fine.

Should DHCP Relaying be enabled for VLAN 1?

Incidentally, I also have IP Helpers set up for DNS, DHCP, Netbios.
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Radhakrishnan RSenior Technical LeadCommented:

Can you have a look at this article http://support.simpledns.com/KB/a45/what-is-reverse-dns-and-do-i-need-it.aspx and see you have the correct reverse lookup zone as the vlan required ptr records in order communicate with server.
abustraanAuthor Commented:
I do. In fact in further testing, I've discovered:

If IP Address is DHCP from Pool for VLAN1 I can ping all but the DNS server via IP address.

If IP Address is static within the DHCP Pool from VLAN 1 I can ping all but the DNS server via IP address.

However, if I statically assign an address to the same subnet as VLAN1 but outside the DHCP Pool, I can reach all servers including DNS by name and IP Address.
abustraanAuthor Commented:
There are 3 things that make up the network address assignment:

DHCP - Obtaining an IP address Automatically
DNS - Resolving that IP address to a name.
ARP - Resolving that IP address to a MAC address.

Through the troubleshooting process I figured out that the DHCP and DNS were good and the ARP was bad. And even though the ARP table is self-maintaining, it can get corrupted and need manual adjusting.
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