Uploaded image for project: 'ZABBIX BUGS AND ISSUES'
  1. ZABBIX BUGS AND ISSUES
  2. ZBX-4252

Agent sends AAAA queries when operating system IPv6 support is disabled

    XMLWordPrintable

Details

    Description

      When using Server=host.domain in zabbix_agentd.conf, the agent sends AAAA queries without IPv6 available on the operating system.

      IPv6 totally disabled using:

      • Kernel command line: ipv6.disable=1
      • sysctl.conf parameters:
        net.ipv6.conf.all.disable_ipv6 = 1
        net.ipv6.conf.default.disable_ipv6 = 1
        net.ipv6.conf.lo.disable_ipv6 = 1
      • ifconfig -a
        eth0 Link encap:Ethernet HWaddr 00:26:36:11:11:a6
        inet addr:192.168.1.13 Bcast:192.168.1.255 Mask:255.255.255.0
        UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
        RX packets:1547619 errors:0 dropped:0 overruns:0 frame:0
        TX packets:1455500 errors:0 dropped:0 overruns:0 carrier:0
        collisions:0 txqueuelen:1000
        RX bytes:139664869 (139.6 MB) TX bytes:132665509 (132.6 MB)

      lo Link encap:Local Loopback
      inet addr:127.0.0.1 Mask:255.0.0.0
      UP LOOPBACK RUNNING MTU:16436 Metric:1
      RX packets:12945 errors:0 dropped:0 overruns:0 frame:0
      TX packets:12945 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:0
      RX bytes:1778023 (1.7 MB) TX bytes:1778023 (1.7 MB)

      tcpdump sample:
      14:01:16.162879 IP 192.168.1.15.53 > 192.168.1.13.44963: 35160 NXDomain* 0/1/0 (98)
      14:01:16.162967 IP 192.168.1.13.59965 > 192.168.1.15.53: 43502+ A? zabbix.elabsis.com. (36)
      14:01:16.163875 IP 192.168.1.15.53 > 192.168.1.13.59965: 43502* 1/2/2 A[|domain]
      14:01:16.292863 IP 192.168.1.13.45479 > 192.168.1.15.53: 3614+ AAAA? zabbix.elabsis.com. (36)
      14:01:16.293466 IP 192.168.1.15.53 > 192.168.1.13.45479: 3614* 0/1/0 (98)
      14:01:16.293538 IP 192.168.1.13.43333 > 192.168.1.15.53: 54497+ AAAA? zabbix.elabsis.com.elabsis.com. (48)
      14:01:16.294384 IP 192.168.1.15.53 > 192.168.1.13.43333: 54497 NXDomain* 0/1/0 (98)
      14:01:16.294435 IP 192.168.1.13.41446 > 192.168.1.15.53: 45609+ A? zabbix.elabsis.com. (36)
      14:01:16.295289 IP 192.168.1.15.53 > 192.168.1.13.41446: 45609* 1/2/2 A[|domain]
      14:01:16.378012 IP 192.168.1.13.50143 > 192.168.1.15.53: 446+ AAAA? zabbix.elabsis.com. (36)
      14:01:16.378635 IP 192.168.1.15.53 > 192.168.1.13.50143: 446* 0/1/0 (98)
      14:01:16.378704 IP 192.168.1.13.53937 > 192.168.1.15.53: 49180+ AAAA? zabbix.elabsis.com.elabsis.com. (48)
      14:01:16.379620 IP 192.168.1.15.53 > 192.168.1.13.53937: 49180 NXDomain* 0/1/0 (98)
      14:01:16.379670 IP 192.168.1.13.54214 > 192.168.1.15.53: 2279+ A? zabbix.elabsis.com. (36)
      14:01:16.380582 IP 192.168.1.15.53 > 192.168.1.13.54214: 2279* 1/2/2 A[|domain]
      14:01:16.450368 IP 192.168.1.13.39695 > 192.168.1.15.53: 61037+ AAAA? zabbix.elabsis.com. (36)
      14:01:16.451051 IP 192.168.1.15.53 > 192.168.1.13.39695: 61037* 0/1/0 (98)
      14:01:16.451329 IP 192.168.1.13.43782 > 192.168.1.15.53: 35967+ AAAA? zabbix.elabsis.com.elabsis.com. (48)
      14:01:16.452111 IP 192.168.1.15.53 > 192.168.1.13.43782: 35967 NXDomain* 0/1/0 (98)
      14:01:16.452192 IP 192.168.1.13.60385 > 192.168.1.15.53: 12860+ A? zabbix.elabsis.com. (36)
      14:01:16.453088 IP 192.168.1.15.53 > 192.168.1.13.60385: 12860* 1/2/2 A[|domain]
      14:01:16.470602 IP 192.168.1.13.37713 > 192.168.1.15.53: 39599+ AAAA? zabbix.elabsis.com. (36)
      14:01:16.471580 IP 192.168.1.15.53 > 192.168.1.13.37713: 39599* 0/1/0 (98)
      14:01:16.471671 IP 192.168.1.13.38240 > 192.168.1.15.53: 34748+ AAAA? zabbix.elabsis.com.elabsis.com. (48)
      14:01:16.472410 IP 192.168.1.15.53 > 192.168.1.13.38240: 34748 NXDomain* 0/1/0 (98)

      Recompiling the agent without the IPv6 support, the AAAA queries donĀ“t occur anymore.

      But if the agent is compiled with IPv6 support (using Debian/Ubuntu package) and IPv6 is disabled on the operating system, AAAA queries are sent anyway, doing extra load on DNS servers.

      Attachments

        Issue Links

          Activity

            People

              andris Andris Mednis
              miguelzinho Miguel Di Ciurcio Filho
              Votes:
              1 Vote for this issue
              Watchers:
              1 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved: