How to sync a Linux secondary DHCP server?

Sten Carlsen stenc at
Tue Jul 31 14:21:08 UTC 2018

Just to clarify, "host reservations" can be two things.

Host statement, possibly with a fixed address statement - synchronized
via file transfer.

Reservation in the leases file - how would these function in a fail over

On 31/07/2018 16.16, Thomas Markwalder wrote:
> Hello Sandra:
> Yes. Anything specified via configuration file must be sync'd outside
> of ISC DHCP.
> Fail over, in ISC DHCP, is based on draft RFC:
> It does not call for exchanging information beyond lease and server
> state information, and
> was written such that any two servers which adhere to it, should be
> inter operable.  At least
> that was the original intent.
> Host reservations are "a policy mechanism" and as such are not
> governed by RFCs. Thus they
> are entirely specific to DHCP server implementations.
> Regards,
> Thomas Markwalder
> ISC Software Engineering
> On 07/31/2018 10:00 AM, Sandra Schlichting wrote:
>>> One point of clarification,  Host reservations are not synchronized
>>> between servers via fail over.  Any host reservations you have in one
>>> configuration file,  you must include in the peer server's
>>> configuration
>>> file.  For dynamic reservations (i.e. those that do not include a fixed
>>> address), the leases allocated for each host will be synchronized
>>> (assuming they come from within a FO pool), but not the actual
>>> reservation specifications.
>> So for the reservation I would have to rsync/scp them over?
>> _______________________________________________
>> dhcp-users mailing list
>> dhcp-users at
> _______________________________________________
> dhcp-users mailing list
> dhcp-users at

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the dhcp-users mailing list