dont-use-fsync real world impact

[sthaug at nethelp.no]

> AIUI failover updates are "instant" but there's a config option to batch them. Similarly IIRC there's now a config option to batch lease file updates/fsyncs ? Both these config options being there to allow adjustment of the performance/security tradeoff.

We have been running a DHCP failover pair with

delayed-ack 28;
max-unacked-updates 10;

for several years, with lease files on battery backed RAID. It has
worked very well for us through those years.

Steinar Haug, Nethelp consulting, sthaug at nethelp.no