Slow DNS (and host: connection timed out)

[Bc. Radek Krejca]

Hi,

  I have similar problem, 3 servers in the same switch, the same
  configuration, but sending of e-mail from php takes very long time,
  but only on 2 servers with 7.1 amd64. On 6.2 (the same ip range,
  the same dns resolver, the same version of php, the same switch) no
  problem.

  Where could be a problem? Resolver? Interesting is that are moments
  when problem isnt on 7.1 too (but very rarely).

  I thing that is problem of version of FBSD but I havent any
  verification yet.

Radek