dns checking [named]

[frater]

Based on the info I got here, I created this script to get info about the speed of the used DNS-server.
It's supposed to find out which IP it should ask to resolve the local DNS-server.

I just finished writing it, but I'm not sure if I covered all situations.
It will always return a number.
On error this is 999999

I welcome feedback

item:

DNS resolve speed
net.tcp.dnsspeed
Numeric (unsigned)
Interval 60

Trigger:

DNS is slow on {HOSTNAME}
{Template_Linux:net.tcp.dnsspeed.max(300)}>50

DNS is not running on {HOSTNAME}
{Template_Linux:net.tcp.dnsspeed.last(0)}>5000

#!/bin/bash
#####################################################
# dnsspeed
#####################################################
#
# echo 'UserParameter=net.tcp.dnsspeed[*],/usr/local/sbin/dnsspeed "$1" "$2"' >>/etc/zabbix/zabbix_agentd.conf
#####################################################
export PATH=${PATH}:/usr/local/sbin:/sbin:/usr/sbin:/bin:/usr/bin

IP=$1
RAWZONE=$2
WAIT=4

[ -z "${RAWZONE}" ] && RAWZONE=pool.ntp.org
ZONE="`echo "${RAWZONE}" | grep '\.' | grep '[A-Za-z0-9.-]*'`"
[ "${RAWZONE}" = "${ZONE}" ] || exit 1

if [ -z "${IP}" ] ; then
  IP=127.0.0.1
elif ! echo "${IP}" | grep -qE '^([0-9]{1,3}\.){3}[0-9]{1,3}$' ; then
  echo 99999
  exit 1
fi

ftmp1=`mktemp`
host -W${WAIT} -Tv ${ZONE} ${IP} 2>/dev/null >${ftmp1}

if [ $? -eq 0 ] && [ -s ${ftmp1} ] ; then
  if grep -q NOERROR ${ftmp1} ; then
    ANSWER=`grep ^Received $ftmp1 | grep -oE ' in [0-9]+ ms' | tail -n1 | awk '{print $2}'`
    if [ ! -z "${ANSWER}" ] ; then
      echo "${ANSWER}"
      rm -f $ftmp1
      exit 0
    fi
  fi
fi
expr ${WAIT} \* 1000 + 1000
rm -f ${ftmp1}

[qix]

@Janis

Can anybody help with NET.TCP.DNS key. I have problems with basic understanding of nslookup key at this point of view. Firstly question I want to use this key for testing if the DNS server is responable, but on which host I have to put this on? On nameserver or on different host which will test the nameserver working condition?

Sorry for the stupid question.

You can use net.tcp.dns[<ip>,zone] on any server. The <ip> adres is the adres of the nameserver that you would like to resolv with, the zone is the zone name that you want to check.

So, for instance, to check if google.com will resolve on a local dns server do:

net.tcp.dns[127.0.0.1,google.com]

For checking if a remote DNS server will resolve zabbix.com:

net.tcp.dns[ip.of.isp.dns,zabbix.com]

[doctorbal82]

Fantastic! I was going to build a script for this but Zabbix already has the supported item type. Thanks for making this clear!

[Rudlafik]

Now: net.dns.record[<ip>,name,<type>,<timeout>,<count>,<protocol>]