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Can anyone take a look at these DNS issue and tell me if any of them are critical and could result in DNS issue (500 errors) and if the fixes that I found online are correct.

1. Max Open Files

 max open files (1024) is smaller than max sockets (4096): 2 Time(s)

Fix according to Google:

  1. Open your named.conf and add the following line to the Options section:

    files 4096;

  2. Open /etc/security/limits.conf and add the following line:

    named soft nofile 4096

2. Network unreachable

network unreachable resolving '': 2001:610:240:0:53::193#53: 1 Time(s)

Fix according to Google:

To fix this you have to start the bind damon with "-4" (IPv4 only). You can add the line "OPTIONS="-4"" to /etc/sysconfig/named to do so.

3. the working directory is not writable

the working directory is not writable: 2 Time(s)

Fix according to Google:

$ sudo chmod g+w named


using default UDP/IPv4 port range: [1024, 65535]: 2 Time(s)
using default UDP/IPv6 port range: [1024, 65535]: 2 Time(s)
client view external: zone transfer 'domain/AXFR/IN' denied: 2 Time(s)

Any help, much appreciated. I already upgraded my kernel via yum, but I am not sure if this will help

Thanks Oliver

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"500 errors"? You are aware that DNS isn't HTTP, right? – womble Jul 30 '11 at 15:12
up vote 0 down vote accepted

The first two could definitely cause intermittent problems; the third should bomb your server fairly completely. All three should be fixed.

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It's not like the server is writing to /var/named all the time, only when the zones are changed, am I right? If so, then it would not "bomb" the server - what are you referring to? – mashup Jul 30 '11 at 15:34
I also found out that this only happens when BIND restarts, so the "not resolving" is probably related to that. And the working directory error is a common bug with WHM… – mashup Jul 30 '11 at 15:36

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