Some .io nameservers are returning wrong results again
IO apears to have nameservers operated by Afilias, CommunityDNS, OneWorld DNS (which appear to also be CommunityDNS)<p><pre><code>    $ for ns in $(dig +short io. IN NS | sort); do
      ip=$(dig +short ${ns} IN A);
      rev=$(host ${ip} | awk -Fpointer &#x27;{print $2}&#x27;);
      echo -n &quot;= $ns = $ip = $rev = &quot;;
      whois -h whois.ripe.net ${ip} | awk -F: &#x27;&#x2F;^descr:&#x2F; &amp;&amp; !&#x2F;RIPE&#x2F; {print $2}&#x27;;
    done
    
    = a0.nic.io. = 65.22.160.17 =  a0.nic.payu. = Afilias NS087 A0
    = b0.nic.io. = 65.22.161.17 =  b0.nic.payu. = Afilias NS087 B0
    = c0.nic.io. = 65.22.162.17 =  c0.nic.payu. = Afilias NS087 C0
    = ns-a1.io. = 194.0.1.1 =  ns1.communitydns.net. = ICB plc Anycast (via NetConnex AS21396), ICB plc Anycast (via Community DNS AS42909)
    = ns-a2.io. = 194.0.2.1 =  ns-a2.io. = ICB plc Anycast (via Community DNS AS42909)
    = ns-a3.io. = 74.116.178.1 =  b3-1.oneworlddns.net. = Community DNS
    = ns-a4.io. = 74.116.179.1 =  b4-1.oneworlddns.net. = Community DNS
</code></pre>
It looks like a couple of the CommunityDNS nameservers are carrying a different version of the zone than the others:<p><pre><code>    dkmpb:~ dknight$ dig -4 +nss io.
    SOA a0.nic.io. noc.afilias-nst.info. 1497256293 10800 3600 2764800 900 from server 65.22.162.17 in 38 ms.
    SOA a0.nic.io. noc.afilias-nst.info. 1497256292 10800 3600 2764800 900 from server 65.22.160.17 in 44 ms.
    SOA a0.nic.io. noc.afilias-nst.info. 1497256201 10800 3600 2764800 900 from server 194.0.2.1 in 62 ms.
    SOA a0.nic.io. noc.afilias-nst.info. 1497256293 10800 3600 2764800 900 from server 194.0.1.1 in 64 ms.
    SOA a0.nic.io. noc.afilias-nst.info. 1497256293 10800 3600 2764800 900 from server 65.22.161.17 in 98 ms.
    SOA a0.nic.io. noc.afilias-nst.info. 1497256293 10800 3600 2764800 900 from server 74.116.178.1 in 101 ms.
    SOA a0.nic.io. noc.afilias-nst.info. 1497256201 10800 3600 2764800 900 from server 74.116.179.1 in 107 ms.
</code></pre>
And a couple of them are giving bad response<p><pre><code>    echo = Afilias
    dig +noall +norecur +cmd +answer +authority -4 +notcp @a0.nic.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS 
    dig +noall +norecur +cmd +answer +authority -4 +notcp @b0.nic.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS 
    dig +noall +norecur +cmd +answer +authority -4 +notcp @c0.nic.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS 
    echo
    echo = Community DNS
    dig +noall +norecur +cmd +answer +authority -4 +notcp @ns-a1.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS 
    dig +noall +norecur +cmd +answer +authority -4 +notcp @ns-a2.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS 
    dig +noall +norecur +cmd +answer +authority -4 +notcp @ns-a3.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS 
    dig +noall +norecur +cmd +answer +authority -4 +notcp @ns-a4.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS
    
    ====== Afilias ======
    
    ; &lt;&lt;&gt;&gt; DiG 9.8.3-P1 &lt;&lt;&gt;&gt; +noall +norecur +cmd +answer +authority -4 +notcp @a0.nic.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS
    ; (1 server found)
    ;; global options: +cmd
    io.			86400	IN	SOA	a0.nic.io. noc.afilias-nst.info. 1497256290 10800 3600 2764800 900
    io.			86400	IN	NS	ns-a3.io.
    io.			86400	IN	NS	b0.nic.io.
    io.			86400	IN	NS	ns-a1.io.
    io.			86400	IN	NS	ns-a4.io.
    io.			86400	IN	NS	ns-a2.io.
    io.			86400	IN	NS	a0.nic.io.
    io.			86400	IN	NS	c0.nic.io.
    hostname.bind.		0	CH	TXT	&quot;ns087b.app22.iad1.afilias-nst.info&quot;
    hostname.bind.		0	CH	NS	hostname.bind.
    shl.io.			86400	IN	NS	ns2.p23.dynect.net.
    shl.io.			86400	IN	NS	ns1.p23.dynect.net.
    shl.io.			86400	IN	NS	ns3.p23.dynect.net.
    shl.io.			86400	IN	NS	ns4.p23.dynect.net.
    shl.io.			86400	IN	NS	ns1.d-zone.ca.
    shl.io.			86400	IN	NS	ns2.d-zone.ca.
    
    ; &lt;&lt;&gt;&gt; DiG 9.8.3-P1 &lt;&lt;&gt;&gt; +noall +norecur +cmd +answer +authority -4 +notcp @b0.nic.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS
    ; (1 server found)
    ;; global options: +cmd
    io.			86400	IN	SOA	a0.nic.io. noc.afilias-nst.info. 1497256290 10800 3600 2764800 900
    io.			86400	IN	NS	ns-a1.io.
    io.			86400	IN	NS	c0.nic.io.
    io.			86400	IN	NS	ns-a3.io.
    io.			86400	IN	NS	a0.nic.io.
    io.			86400	IN	NS	ns-a2.io.
    io.			86400	IN	NS	ns-a4.io.
    io.			86400	IN	NS	b0.nic.io.
    hostname.bind.		0	CH	TXT	&quot;ns087b.app12.lax1.afilias-nst.info&quot;
    hostname.bind.		0	CH	NS	hostname.bind.
    shl.io.			86400	IN	NS	ns2.d-zone.ca.
    shl.io.			86400	IN	NS	ns1.p23.dynect.net.
    shl.io.			86400	IN	NS	ns1.d-zone.ca.
    shl.io.			86400	IN	NS	ns4.p23.dynect.net.
    shl.io.			86400	IN	NS	ns2.p23.dynect.net.
    shl.io.			86400	IN	NS	ns3.p23.dynect.net.
    
    ; &lt;&lt;&gt;&gt; DiG 9.8.3-P1 &lt;&lt;&gt;&gt; +noall +norecur +cmd +answer +authority -4 +notcp @c0.nic.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS
    ; (1 server found)
    ;; global options: +cmd
    io.			86400	IN	SOA	a0.nic.io. noc.afilias-nst.info. 1497256290 10800 3600 2764800 900
    io.			86400	IN	NS	ns-a1.io.
    io.			86400	IN	NS	c0.nic.io.
    io.			86400	IN	NS	ns-a4.io.
    io.			86400	IN	NS	ns-a2.io.
    io.			86400	IN	NS	ns-a3.io.
    io.			86400	IN	NS	b0.nic.io.
    io.			86400	IN	NS	a0.nic.io.
    hostname.bind.		0	CH	TXT	&quot;ns087b.app25.iad1.afilias-nst.info&quot;
    hostname.bind.		0	CH	NS	hostname.bind.
    shl.io.			86400	IN	NS	ns4.p23.dynect.net.
    shl.io.			86400	IN	NS	ns2.d-zone.ca.
    shl.io.			86400	IN	NS	ns2.p23.dynect.net.
    shl.io.			86400	IN	NS	ns1.d-zone.ca.
    shl.io.			86400	IN	NS	ns1.p23.dynect.net.
    shl.io.			86400	IN	NS	ns3.p23.dynect.net.

    ====== Community DNS ======
    
    ; &lt;&lt;&gt;&gt; DiG 9.8.3-P1 &lt;&lt;&gt;&gt; +noall +norecur +cmd +answer +authority -4 +notcp @ns-a1.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS
    ; (1 server found)
    ;; global options: +cmd
    io.			86400	IN	SOA	a0.nic.io. noc.afilias-nst.info. 1497256290 10800 3600 2764800 900
    hostname.bind.		0	CH	TXT	&quot;NORM 002590-E2B186&quot;
    shl.io.			86400	IN	NS	ns1.d-zone.ca.
    shl.io.			86400	IN	NS	ns2.d-zone.ca.
    shl.io.			86400	IN	NS	ns1.p23.dynect.net.
    shl.io.			86400	IN	NS	ns2.p23.dynect.net.
    shl.io.			86400	IN	NS	ns3.p23.dynect.net.
    shl.io.			86400	IN	NS	ns4.p23.dynect.net.
    
    ; &lt;&lt;&gt;&gt; DiG 9.8.3-P1 &lt;&lt;&gt;&gt; +noall +norecur +cmd +answer +authority -4 +notcp @ns-a2.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS
    ; (1 server found)
    ;; global options: +cmd
    io.			86400	IN	SOA	a0.nic.io. noc.afilias-nst.info. 1497256201 10800 3600 2764800 900
    hostname.bind.		0	CH	TXT	&quot;COMM 002590-E2B186&quot;
    io.			900	IN	SOA	a0.nic.io. noc.afilias-nst.info. 1497256201 10800 3600 2764800 900
    
    ; &lt;&lt;&gt;&gt; DiG 9.8.3-P1 &lt;&lt;&gt;&gt; +noall +norecur +cmd +answer +authority -4 +notcp @ns-a3.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS
    ; (1 server found)
    ;; global options: +cmd
    io.			86400	IN	SOA	a0.nic.io. noc.afilias-nst.info. 1497256290 10800 3600 2764800 900
    hostname.bind.		0	CH	TXT	&quot;NORM 001B24-2DB609&quot;
    shl.io.			86400	IN	NS	ns1.d-zone.ca.
    shl.io.			86400	IN	NS	ns2.d-zone.ca.
    shl.io.			86400	IN	NS	ns1.p23.dynect.net.
    shl.io.			86400	IN	NS	ns2.p23.dynect.net.
    shl.io.			86400	IN	NS	ns3.p23.dynect.net.
    shl.io.			86400	IN	NS	ns4.p23.dynect.net.
    
    ; &lt;&lt;&gt;&gt; DiG 9.8.3-P1 &lt;&lt;&gt;&gt; +noall +norecur +cmd +answer +authority -4 +notcp @ns-a4.io. io. IN SOA hostname.bind. CH TXT shl.io. IN NS
    ; (1 server found)
    ;; global options: +cmd
    io.			86400	IN	SOA	a0.nic.io. noc.afilias-nst.info. 1497256201 10800 3600 2764800 900
    hostname.bind.		0	CH	TXT	&quot;COMM 001B24-2DB609&quot;
    io.			900	IN	SOA	a0.nic.io. noc.afilias-nst.info. 1497256201 10800 3600 2764800 900</code></pre>