Reverse lookup SERVFAIL
- by Quan Tran
I just set up a DNS server and a web server using Virtualbox. The IP address of the DNS server is 192.168.56.101 and the web server 192.168.56.102.
Here are my configuration files for the DNS server:
named.conf:
//
// named.conf
//
// Provided by Red Hat bind package to configure the ISC BIND named(8) DNS
// server as a caching only nameserver (as a localhost DNS resolver only).
//
// See /usr/share/doc/bind*/sample/ for example named configuration files.
//
options {
directory "/var/named";
dump-file "/var/named/data/cache_dump.db";
statistics-file "/var/named/data/named_stats.txt";
memstatistics-file "/var/named/data/named_mem_stats.txt";
//query-source address * port 53;
//forward first;
forwarders { 8.8.8.8; 8.8.4.4; };
listen-on port 53 { 127.0.0.1; 192.168.56.0/24; };
allow-query { localhost; 192.168.56.0/24; };
recursion yes;
dnssec-enable yes;
dnssec-validation yes;
dnssec-lookaside auto;
/* Path to ISC DLV key */
bindkeys-file "/etc/named.iscdlv.key";
managed-keys-directory "/var/named/dynamic";
};
logging {
channel default_debug {
file "data/named.run";
severity debug 10;
print-category yes;
print-time yes;
print-severity yes;
};
};
zone "quantran.com" in {
type master;
file "named.quantran.com";
};
zone "56.168.192.in-addr.arpa" in {
type master;
file "named.192.168.56";
allow-update { none; };
};
include "/etc/named.rfc1912.zones";
include "/etc/named.root.key";
named.quantran.com:
$TTL 86400
quantran.com. IN SOA dns1.quantran.com. root.quantran.com. (
100 ; serial
3600 ; refresh
600 ; retry
604800 ; expire
86400 )
IN NS dns1.quantran.com.
dns1.quantran.com. IN A 192.168.56.101
www.quantran.com. IN A 192.168.56.102
named.192.168.56:
$TTL 86400
$ORIGIN 56.168.192.in-addr.arpa.
@ IN SOA dns1.quantran.com. root.quantran.com. (
100 ; serial
3600 ; refresh
600 ; retry
604800 ; expire
86400 ) ; minimum
IN NS dns1.quantran.com.
101.56.168.192.in-addr.arpa. IN PTR dns1.quantran.com.
102 IN PTR www.quantran.com.
When I try a normal lookup from the host (I configured so that the only nameserver the host uses is the DNS server 192.168.56.101):
quan@quantran:~$ host www.quantran.com
www.quantran.com has address 192.168.56.102
quan@quantran:~$ host dns1.quantran.com
dns1.quantran.com has address 192.168.56.101
But when I try a reverse lookup:
quan@quantran:~$ host -v 192.168.56.101 192.168.56.101
Trying "101.56.168.192.in-addr.arpa"
Using domain server:
Name: 192.168.56.101
Address: 192.168.56.101#53
Aliases:
Host 101.56.168.192.in-addr.arpa not found: 2(SERVFAIL)
Received 45 bytes from 192.168.56.101#53 in 0 ms
quan@quantran:~$ host -v 192.168.56.102 192.168.56.101
Trying "102.56.168.192.in-addr.arpa"
Using domain server:
Name: 192.168.56.101
Address: 192.168.56.101#53
Aliases:
Host 102.56.168.192.in-addr.arpa not found: 2(SERVFAIL)
Received 45 bytes from 192.168.56.101#53 in 0 ms
So why can't I perform a reverse lookup? Anything wrong with the zone configuration files?
Thanks in advance :)
Oh, here is the output from the log file /var/named/data/named.run when I perform the reverse lookup:
quan@quantran:~$ host 192.168.56.102 192.168.56.101
Using domain server:
Name: 192.168.56.101
Address: 192.168.56.101#53
Aliases:
Host 102.56.168.192.in-addr.arpa not found: 2(SERVFAIL)
/var/named/data/named.run:
02-Jun-2014 15:18:11.950 client: debug 3: client 192.168.56.1#51786: UDP request
02-Jun-2014 15:18:11.950 client: debug 5: client 192.168.56.1#51786: using view '_default'
02-Jun-2014 15:18:11.950 security: debug 3: client 192.168.56.1#51786: request is not signed
02-Jun-2014 15:18:11.950 security: debug 3: client 192.168.56.1#51786: recursion available
02-Jun-2014 15:18:11.950 client: debug 3: client 192.168.56.1#51786: query
02-Jun-2014 15:18:11.950 client: debug 10: client 192.168.56.1#51786: ns_client_attach: ref = 1
02-Jun-2014 15:18:11.950 query-errors: debug 1: client 192.168.56.1#51786: query failed (SERVFAIL) for 102.56.168.192.in-addr.arpa/IN/PTR at query.c:5428
02-Jun-2014 15:18:11.950 client: debug 3: client 192.168.56.1#51786: error
02-Jun-2014 15:18:11.950 client: debug 3: client 192.168.56.1#51786: send
02-Jun-2014 15:18:11.950 client: debug 3: client 192.168.56.1#51786: sendto
02-Jun-2014 15:18:11.951 client: debug 3: client 192.168.56.1#51786: senddone
02-Jun-2014 15:18:11.951 client: debug 3: client 192.168.56.1#51786: next
02-Jun-2014 15:18:11.951 client: debug 10: client 192.168.56.1#51786: ns_client_detach: ref = 0
02-Jun-2014 15:18:11.951 client: debug 3: client 192.168.56.1#51786: endrequest
02-Jun-2014 15:18:11.951 client: debug 3: client @0xb537e008: udprecv
Also, I made some changes to the log section in named.conf.
