dhclient: lease renewal woes

Steve Clark sclark at netwolves.com
Sun Sep 9 16:40:52 UTC 2012

On 09/09/2012 10:06 AM, Sten Carlsen wrote:
> Fixing a broken ISP implementation by breaking the client implementation?
> I guess that is a fair deal? Maybe I should try that with some of the public utilities?
> On 09/09/12 15:54, Mr Dash Four wrote:
>>> You should not blame the software for your ISP having a rubbish network.
>> I don't, but I expect that every decently written piece of software to have a "plan B" which could be deployed - swiftly - if "plan A" doesn't seem to work. That, evidently, isn't happening with dhclient.
>>> Incidentally, did you ever figure out why the client was not renewing by broadcast at around 7/8 of the lease time which is what I assume it's doing now ?
>> A couple of factors, one being that the server specified in the server ID given in the lease acknowledgement is not responding to direct requests, which is what dhclient was doing (instead of switching to either a broadcast or the dhcp agent giving the lease in the first place).
>> Another thing I've changed were these pre-defined periods - by default the lease renewal takes place when about 1/2 of the lease is still valid, and rebinds when 7/8 of that lease time has lapsed, give or take a randomly pre-selected interval. That may seem fine with short leases, but when the lease is long, the gap between 1/2 and 7/8 is quite a big one, so that is another thing I altered. It is all working now, so I am content with using dhclient for the time being. My "plan B" (yes, I do have one) was to switch to dhcpcd, if I couldn't fix the above problems.
>> _______________________________________________
>> dhcp-users mailing list
>> dhcp-users at lists.isc.org
>> https://lists.isc.org/mailman/listinfo/dhcp-users
> -- 
> Best regards
> Sten Carlsen
You are obviously from the world of academia - where theory is more important
than a working system.
> No improvements come from shouting:
>         "MALE BOVINE MANURE!!!"
> _______________________________________________
> dhcp-users mailing list
> dhcp-users at lists.isc.org
> https://lists.isc.org/mailman/listinfo/dhcp-users

Stephen Clark
Director of Technology
Phone: 813-579-3200
Fax: 813-882-0209
Email: steve.clark at netwolves.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.isc.org/pipermail/dhcp-users/attachments/20120909/8dcdfda4/attachment-0001.html>

More information about the dhcp-users mailing list