Issues w/Failover between 2k8 R2 + w2k3 R2.

Hi,

I'll give an overview of the setup first.

server 1 = w2k8 R2
server 2 = w2k3 R2

Server 1 is the primary DHCP server, also running AD/DNS
Server 2 will be the failover DHCP, also running AD/DNS

both servers are on the same /24 network, no firewall/routers are between...

I've setup DHCP redundancy as per the setup guide and configured/installed service, upon stopping the DHCP service on server1, the fail-over occurs, and the DHCP service is started on server2, however no scope is imported.

I've confirmed the export is copying across from server1 to server2 (by watching the update time of the dhcp export txt file created by the scheduled dhcp backup task) and by manually copying across the file (using the correct filename)

in addition to the above, I've confirmed the fail-back upon the server1's DHCP server going live again works.. Although, further testing shows this doesn't always happen? - sometimes it reports :

Start of main routine
Status of Update value= No
Querying status of main DHCP service
Result of query= unable to determine the dhcp server version for the server <server 1 ip>.
Main DHCP service is down
Main DHCP service was down the last check too, quiting main routine
End of main routine

That aside,
But still no scope imported.. on the off chance it was a permissions issue, i've changed the service from a local/network account to that of a domain admin account w/Login as service etc rights - same thing..

Debugging is enabled, and nothing in there appears to be wrong - a sample is below..

inished reading settings from the registry
MainDHCPserver= <server 1 ip>
Mailsender= <email address>
Mailserver= <mail server>
SMTPAuthentication= No
SendUPmail= yes
FilePath= \\<server 2 ip>\c$\Program Files\dhcp-redundancy\
DownMailBody=
UpMailBody=
DownMailHeader=
UpMailHeader
Start of main routine
Status of Update value= No
Querying status of main DHCP service
Result of query= the current server is <server 1 ip> with ip address = <server 1 ip>
The main DHCP service is up
End of main routine

~

Start of main routine
Status of Update value= No
Querying status of main DHCP service
Result of query= unable to determine the dhcp server version for the server <server 1 ip>.
Main DHCP service is down
No new DHCP backup
Start the secondary DHCP service
Secondary DHCP service has started
->Event log: DHCP-service on server <server 1 ip> is not functionalling, starting redundant DHCP-Service
Sending mail that the main DHCP service is down
Mail sent
Quiting the main routine
End of main routine

Start of main routine
Status of Update value= No
Querying status of main DHCP service
Result of query= unable to determine the dhcp server version for the server <server 1 ip>
Main DHCP service is down
Main DHCP service was down the last check too, quiting main routine
End of main routine


Start of main routine
Status of Update value= No
Querying status of main DHCP service
Result of query= the current server is <server 1 ip> with ip address = <server1 ip>
The main DHCP service is up
Sending mails that the main DHCP service is up
->Event log: DHCP-service on server <server 1 ip> is functionalling, stopped redundant DHCP-Service
Mail sent
End of main routine

let me know if there is any further info you need or if there is any way I can help - thanks

Hi.

Sorry for late reply.

The line 'No new DHCP backup' indicates that the redundancy service cant find the dhcp backup files.
Start the DHCP Redundancy Config and verify the ' Directory of DHCP-Redundancy files' is the directory where the backup file are.
Also the backup file must be named DHCP-Backup.txt

Hi - No problems, your assistance is greatly appreciated

The file is being created by the export batch running on the primary DHCP server and the file name is as per specified and in the exact same case.

I've tried setting the path to the files via the config util to both the UNC and the local disk path, but I get the same result.

To test, I tried to import the exported DHCP (2008 R2) file into the 2003 R2 DHCP server - with this response...

netsh dhcp server>import "C:\Program Files\dhcp-redundancy\DHCP-Backup.txt" all
The request is not supported.

From what I can gather, it may be that the 2008 R2 DHCP export is not compatible with 2003 R2 import ??

You should not include the > in the command, it should be:

netsh dhcp server import "C:\Program Files\dhcp-redundancy\DHCP-Backup.txt" all

If that doesn't work, it's probaply as you write, you cant import a server 2008 backup on a server 2003. I dont have a lab to test this scenario...
The other way around works though.

Can you upgrade the server 2003 to a 2008? So you have two 2008, that should work fine.

Thanks for the reply - the > is not included in the command, I'm just already in the dhcp server context when I ran the command..

Sadly, not possible to replace the secondary dhcp server with a 2k8 server - I will look to find a method to export an compatible dhcp export backup..

Check if it possible to export just the IPv4 part of the DHCP.