Thread: Bind DNS Query Per Second - bindgraph.cgi not working in RHEL / CentOS Linux

Hi,

We are running caching only dns server for our broadband internet customers.How to find query per second for our dns traffic and how to we find cache hit ratio for caching dns server?

Is there any tool or application by which we have statistics?

Regards,
Rocky J.

You can use dnstop command or bindgrap that makes pretty graphs about queries (such as A, MX, AAAA, TXT and so on) sent to your BIND name server. Both tool works with caching dns server as well as authoritative dns servers.

• FreeBSD: Install bindgraph To Make Graphs About Queries Sent To BIND
• dnstop: Monitor BIND DNS Server (DNS Network Traffic) From a Shell Prompt

Hi Vivek,

Thanks for your reply.I go throw your given both link and those are helpful to understand live dns query / response.

Do we get statistics like which sites are cached by DNS? Does bind support 8000 QPS?

Regards,
Rocky J.

Hi,
check the dump-file statement in named.conf and run "rndc dumpdb" command then all sites which is cached by dns it will store in your disk (dump-file "/path/of/dump/file").

check this link for bind QPS

Hi rocky,

Do we get statistics like which sites are cached by DNS?

use following script to achieve the save

PHP Code:

#!/bin/bash
DUMP_FILE="/var/named/chroot/var/cache.dump"
RNDC="/usr/sbin/rndc"
${RNDC} dumpdb

CNAME=$(grep answer -A1 ${DUMP_FILE} | grep -Ev "answer|--" | awk '{print $3}' | grep ^CNAME | wc -l)
A=$(grep answer -A1 ${DUMP_FILE} | grep -Ev "answer|--" | awk '{print $3}' | grep ^A | wc -l)

echo "+++ Statistics Dump +++"
echo "A         Records : $A"
echo "CNAME     Records : $CNAME"
echo "Total     Records : $(($CNAME + $A))" 


Yes, all sort of stats.

Hi Vivek,

Thanks for your kind response.I followed your tutorial bindgraph on centos , i set bindgraph but when i opened cgi file from browser it shows blank , i mean no graph images and as per .cgi file i set rrd file location and images location but images not happening.

What could be mistake?
bind version : 9.3

Regards,
Rocky J.

Check your Apache cgi-bin config and Apache access/error log file.

Hi Vivek,

There is no error in apache error log.And access log shows,

127.0.0.1 - - [08/May/2012:15:50:02 +0530] "GET / HTTP/1.0" 403 3985 "-" "Wget/1.11.4 Red Hat modified"
10.115.1.90 - - [08/May/2012:15:50:04 +0530] "GET /cgi-bin/bindgraph/bindgraph.cgi HTTP/1.1" 200 913 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20100101 Firefox/12.0"
10.115.1.90 - - [08/May/2012:15:50:04 +0530] "GET /cgi-bin/bindgraph/bindgraph.cgi/bindgraph_1.png HTTP/1.1" 200 301 "http://10.115.1.230/cgi-bin/bindgraph/bindgraph.cgi" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20100101 Firefox/12.0"
10.115.1.90 - - [08/May/2012:15:50:04 +0530] "GET /cgi-bin/bindgraph/bindgraph.cgi/bindgraph_2.png HTTP/1.1" 200 301 "http://10.115.1.230/cgi-bin/bindgraph/bindgraph.cgi" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20100101 Firefox/12.0"
10.115.1.90 - - [08/May/2012:15:50:04 +0530] "GET /cgi-bin/bindgraph/bindgraph.cgi/bindgraph_0.png HTTP/1.1" 200 301 "http://10.115.1.230/cgi-bin/bindgraph/bindgraph.cgi" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20100101 Firefox/12.0"
10.115.1.90 - - [08/May/2012:15:50:04 +0530] "GET /cgi-bin/bindgraph/bindgraph.cgi/bindgraph_3.png HTTP/1.1" 200 301 "http://10.115.1.230/cgi-bin/bindgraph/bindgraph.cgi" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20100101 Firefox/12.0"
10.115.1.90 - - [08/May/2012:15:50:04 +0530] "GET /cgi-bin/bindgraph/bindgraph.cgi/bindgraph_4.png HTTP/1.1" 200 301 "http://10.115.1.230/cgi-bin/bindgraph/bindgraph.cgi" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20100101 Firefox/12.0"

I am using default apache config, there is no change for cgi-bin in apache conf.

i set below parameter in bindgraph.cgi ,

# hostname. will be printed in the HTML page
my $hostname = 'test.example.com';
# path of the RRD database
my $rrd = '/var/www/bindgraph/bindgraph.rrd';
# temporary directory where the images will be saved
my $tmp_dir = '/var/www/bindgraph';

it creates directory ( ,cgi-bin,bindgraph,bindgraph.cgi) inside /var/www/bindgraph , but no graph images there.

Thanks,
Rocky J

What about error_log file? Are you using kernel security feature such as SELinux? If so SELinux may block access to bind log files.