On Fri, Sep 03, 2021 at 12:08:20PM +0100, Ed W wrote: > On 03/09/2021 11:31, Chris Green wrote: > > Two questions really:- > > > > Is the file /var/lib/misc/dnsmasq.leases the only place where > > dnsmasq keeps DHCP/IP/Name information across restarts? I.e. if I > > delete that file will new DHCP requests get new IPs? (or does the > > client have some memory of the last IP it got?) > > > > > > If a client's DHCP lease expires and it sends a new DHCP request > > out, which fails, will it continue to use the old values or will > > it just die? > > > > > > I realise /var/lib/misc/dnsmasq.leases is not cast in stone and could > > be a different file but I'm sure it's clear what question I'm asking. > > > > My understanding is yes to this. > > Dnsmasq keeps it's database completely in ram while running. It updates > the disk "periodically" (ie > whenever the in ram changes), and calls some external events at the same time. > > To be precise I believe you need to first stop dnsmasq before erasing the > disk cache (however, I > regularly get away with doing so while it's running... ;-) ) > I wasn't considering erasing/deleting the dnsmasq.leases file, I was rather thinking of copying it to a non-running backup dnsmasq so that if/when the running dnsmasq fails I can start the other and it will give out the same IPs.
The only other issue is then how to tell 'everyone' that the DNS server has changed address. It's a pity that one can't associate an RJ-45 socket with a specific IP address! :-) -- Chris Green _______________________________________________ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk https://lists.thekelleys.org.uk/cgi-bin/mailman/listinfo/dnsmasq-discuss
