On 5/06/2014 8:14 a.m., Antony Stone wrote: > On Wednesday 04 June 2014 at 21:03, Nidal Shater wrote: > >> I read about "log_fqdn" >> >> Turn this on if you wish to log fully qualified domain names >> in the access.log. To do this Squid does a DNS lookup of all >> IP's connecting to it. This can (in some situations) increase >> latency, which makes your cache seem slower for interactive >> browsing. >> >> Is this very bad to the performance or it has a little effect, because of >> DNS looks up ? > > That's an impossible question to answer with any accuracy, because it depends > on how efficient the DNS lookups are.
Alongside the latency issue it also makes troubleshooting network problems much more difficult if the client or server has multiple IPs. Which is a very common situation to be in given that any machine can have 1+ IPv4 addresses and 3+ IPv6 addresses. As a rule of thumb: if you don't actively need it for some reason, leave the default. Amos
