PHP internals and host resolvment

[toma42]

http://php.net/manual/en/function.gethostbyaddr.php
which uses php_gethostbyaddr which uses two system? functions:
inet_addr() and gethostbyaddr()

Do lookups from shell produce differnet results than php?

[melvyn]

well - I'm no C-Programmer, but a standard nslookup, will query the right server and php doesn't.

If you could write a little test-c program that uses gethostbyname function call, I can test if the environment my be screwed somehow. We do run the server chrooted, but have copied all the files mentioned in man 3 gethostbyaddr to their appropreate locations.

I also copied an instance of the nslookup program into the environment, and it used the correct server. Switching the order in /etc/resolv.conf immediately changed the default server.

[melvyn]

Does anybody know how PHP handles host resolvment? In our environment, it totally seems to disregard /etc/hosts as well as /etc/resolv.conf and takes the backup server (which is in another ip-segment on another line etc etc) instead of the server right above it in the server-cabinet, which is set as primary in resolv.conf.

Alternatively it keeps looking up the mysql host to connect to, and doesn't use any caching as far as I can see from the Bind logging.