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New Member

CNR DHCP Failover ...


I am currently running CNR version 5.5.4 and I need to setup a symmetric DHCP failover on our network. There is a document on how to setup the symmetric failover. But, it did not go into how to configure the "DHCP Helper" as I assume that the CNR-DHCP "main" server and "backup" server will have different IP addresses.

Since, we have quite a few buildings connected via a routers. We have configured a "DHCP Helper" so the clients from a different subnets other than the CNR-DHCP server can obtain an IP address.

My questions is ... do I need to configured the "DHCP Helper" with the IP addresses for the main and backup CNR-DHCP server. So, if either one server failed ... the clients can contact the other and obtain the IP address? Is that how the "Symmetric DHCP" failover works?

Any help or suggestions should be appreciated.

  • Other Network Infrastructure Subjects
New Member

Re: CNR DHCP Failover ...

You will need to set up helper address for both the main and the backup server. This way the same request will be sent to both the servers. The server will decide whether to respond to that client or not based on local failover state.

New Member

Re: CNR DHCP Failover ...

Thanks. I assumed that Cisco routers allowing multiple IP addresses entry for DHCP Helper option?

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