BUG/MINOR: server: Set server without addr but with dns in RMAINT on startup

On startup, if a server has no address but the dns resolutions are configured,
"none" method is added to the default init-addr methods, in addition to "last"
and "libc". Thus on startup, this server is set to RMAINT mode if no address is
found. It is only performed if no other init-addr method is configured.

Setting the RMAINT mode on startup is important to inhibit the health checks.

For instance, following servers will now be set to RMAINT mode on startup :

  server srv nofound.tld:80 check resolvers mydns
  server srv _http._tcp.service.local check resolvers mydns
  server-template srv 1-3 _http._tcp.service.local check resolvers mydns

while followings ones will trigger an error :

  server srv nofound.tld:80 check
  server srv nofound.tld:80 check resolvers mydns init-addr libc
  server srv _http._tcp.service.local check
  server srv _http._tcp.service.local check resolvers mydns init-addr libc
  server-template srv 1-3 _http._tcp.service.local check resolvers mydns init-addr libc

This patch must be backported as far as 1.8.
1 file changed