<div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div><div dir="ltr" class="gmail_signature"><br></div></div></div><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Apr 12, 2019 at 12:37 PM Paul A <<a href="mailto:razor@meganet.net">razor@meganet.net</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Mark, per my previous email, this high latency only happens when digging for<br>
Comcast. I did not compile bind on this machine, I'm using the latest Bind<br>
package that came with CentOS 7, bind-chroot-9.9.4-73.el7_6.x86_64. Looking<br>
at the changelog for the RPM it doesn't mention any issue with dig and<br>
latency and I assume this has been patched by Redhat at some point. <br>
<br>
I just wanted to verify that what Im seeing with Comcast is somehow not<br>
related to only me and someone else is seeing this issue. The lastest dig I<br>
did came back with <br>
"dig: couldn't get address for '<a href="http://dns101.comcast.net" rel="noreferrer" target="_blank">dns101.comcast.net</a>': no more" so I doubt<br>
it's a dig version issue. <br>
<br>
Paul <br>
<br>
<br>
;; Received 239 bytes from 192.5.6.30#53(192.5.6.30) in 32 ms<br>
<br>
net. 172800 IN NS <a href="http://k.gtld-servers.net" rel="noreferrer" target="_blank">k.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://b.gtld-servers.net" rel="noreferrer" target="_blank">b.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://l.gtld-servers.net" rel="noreferrer" target="_blank">l.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://a.gtld-servers.net" rel="noreferrer" target="_blank">a.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://m.gtld-servers.net" rel="noreferrer" target="_blank">m.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://c.gtld-servers.net" rel="noreferrer" target="_blank">c.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://i.gtld-servers.net" rel="noreferrer" target="_blank">i.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://e.gtld-servers.net" rel="noreferrer" target="_blank">e.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://d.gtld-servers.net" rel="noreferrer" target="_blank">d.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://g.gtld-servers.net" rel="noreferrer" target="_blank">g.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://h.gtld-servers.net" rel="noreferrer" target="_blank">h.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://j.gtld-servers.net" rel="noreferrer" target="_blank">j.gtld-servers.net</a>.<br>
net. 172800 IN NS <a href="http://f.gtld-servers.net" rel="noreferrer" target="_blank">f.gtld-servers.net</a>.<br>
net. 86400 IN DS 35886 8 2<br>
7862B27F5F516EBE196804<br>
44D4CE5E762981931842C465F00236401D 8BD973EE<br>
net. 86400 IN RRSIG DS 8 1 86400 20190425050000<br>
2019<br>
0412040000 25266 . Uk5bsrr1dgoBFUYfzSYTi6D+QXow1CZglnE3BUZ7I/I0HjuywiSf2YLx<br>
eU1c<br>
rjlYOJQdYPxDFQIH5/aItTtrM7wgvTOhfhHPHQuAj2f8ovYIlwCt<br>
hguq+9jcNTMAzrUXvi6Tb8oTb36<br>
lprYIfg21yO1d8RO6cx3L0dJMcuez<br>
WN2kxNAg+wrx+dWbOexFO7Hs0gzDPpsMx0lEOkJHcfyb/V71An<br>
MV+nob 48G/azRzQ2fJfs849OyYmjTXA88bAcxxz3kNCoddOfWuMU+WKV5Lfy7J<br>
NkegEfRCzRZYYKiD<br>
MwI0zURTg+CdZAYKuxvJQW9ddzSiK5UnYXZVSO1d fPXfYQ==<br>
;; Received 1168 bytes from 199.9.14.201#53(<a href="http://b.root-servers.net" rel="noreferrer" target="_blank">b.root-servers.net</a>) in 88 ms<br>
<br>
<a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 172800 IN NS <a href="http://dns101.comcast.net" rel="noreferrer" target="_blank">dns101.comcast.net</a>.<br>
<a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 172800 IN NS <a href="http://dns102.comcast.net" rel="noreferrer" target="_blank">dns102.comcast.net</a>.<br>
<a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 172800 IN NS <a href="http://dns103.comcast.net" rel="noreferrer" target="_blank">dns103.comcast.net</a>.<br>
<a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 172800 IN NS <a href="http://dns104.comcast.net" rel="noreferrer" target="_blank">dns104.comcast.net</a>.<br>
<a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 172800 IN NS <a href="http://dns105.comcast.net" rel="noreferrer" target="_blank">dns105.comcast.net</a>.<br>
<a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 86400 IN DS 40909 5 2<br>
30C0F50E68DCC9A2F279A9<br>
94C07CF22CED97AADF44C2B1FE38A1B32B A1A34174<br>
<a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 86400 IN DS 40909 5 1<br>
DDC19733884EE533B35B4B<br>
57717BEA9B0EF2C4D1<br>
<a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 86400 IN RRSIG DS 8 2 86400 20190417054136<br>
2019<br>
0410043136 51638 net.<br>
l2Vj2W+qzAziqzcC+Y+t4+6b6ADTwyILCzbySVmj5mj5J9vscR4mYf+f X<br>
zNGKen73GecLw+HiwwSzUG8jYkGtvNOMrj9ZbC4v+XWuq0EFcxDEhbJ<br>
yTAq2wPMGD6evSUSDLfqYu8h<br>
oJH9svqS06KlBjWkKQqx8X+ZIIqmUMVk ivk=<br>
dig: couldn't get address for '<a href="http://dns101.comcast.net" rel="noreferrer" target="_blank">dns101.comcast.net</a>': no more<br>
<br>
-----Original Message-----<br>
From: Mark Andrews [mailto:<a href="mailto:marka@isc.org" target="_blank">marka@isc.org</a>] <br>
Sent: Friday, April 12, 2019 11:20 AM<br>
To: Paul A <<a href="mailto:razor@meganet.net" target="_blank">razor@meganet.net</a>><br>
Cc: <a href="mailto:bind-users@lists.isc.org" target="_blank">bind-users@lists.isc.org</a> <<a href="mailto:bind-users@isc.org" target="_blank">bind-users@isc.org</a>><br>
Subject: Re: dns latency<br>
<br>
Before you pay attention to the round trip time you need this fix from BIND<br>
9.9.6 from nearly 5 years ago now (2014-07-31).<br>
<br>
3903. [bug] Improve the accuracy of DiG's reported round trip<br>
time. [RT 36611]<br>
<br>
Mark<br>
<br>
> On 13 Apr 2019, at 12:59 am, Paul A <<a href="mailto:razor@meganet.net" target="_blank">razor@meganet.net</a>> wrote:<br>
> <br>
> This is not really a Bind issue, but can anyone else confirm latency <br>
> when querying Comcast from the root down? I ask because this morning some<br>
of our customers Could not email @comcast addresses, looked at the mail<br>
server and domain not found. I suspect my cache for Comcast timeout and when<br>
my DNS server tried doing a new query it timeout on GTLD server to Comcast?<br>
> <br>
> When I query directly to their DNS servers there is no latency, so I<br>
suspect this is a link issue at Comcast affecting DNS?<br>
> <br>
> TIA paul<br>
> <br>
> <br>
> <br>
> ; <<>> DiG 9.9.4-RedHat-9.9.4-61.el7_5.1 <<>> @<a href="http://192.5.6.30" rel="noreferrer" target="_blank">192.5.6.30</a> <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a> <br>
> -t a +trace ; (1 server found) ;; global options: +cmd<br>
> . 518400 IN NS <a href="http://i.root-servers.net" rel="noreferrer" target="_blank">i.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://j.root-servers.net" rel="noreferrer" target="_blank">j.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://k.root-servers.net" rel="noreferrer" target="_blank">k.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://l.root-servers.net" rel="noreferrer" target="_blank">l.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://m.root-servers.net" rel="noreferrer" target="_blank">m.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://a.root-servers.net" rel="noreferrer" target="_blank">a.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://b.root-servers.net" rel="noreferrer" target="_blank">b.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://c.root-servers.net" rel="noreferrer" target="_blank">c.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://d.root-servers.net" rel="noreferrer" target="_blank">d.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://e.root-servers.net" rel="noreferrer" target="_blank">e.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://f.root-servers.net" rel="noreferrer" target="_blank">f.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://g.root-servers.net" rel="noreferrer" target="_blank">g.root-servers.net</a>.<br>
> . 518400 IN NS <a href="http://h.root-servers.net" rel="noreferrer" target="_blank">h.root-servers.net</a>.<br>
> ;; Received 239 bytes from 192.5.6.30#53(192.5.6.30) in 32 ms<br>
> <br>
> net. 172800 IN NS <a href="http://a.gtld-servers.net" rel="noreferrer" target="_blank">a.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://b.gtld-servers.net" rel="noreferrer" target="_blank">b.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://c.gtld-servers.net" rel="noreferrer" target="_blank">c.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://d.gtld-servers.net" rel="noreferrer" target="_blank">d.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://e.gtld-servers.net" rel="noreferrer" target="_blank">e.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://f.gtld-servers.net" rel="noreferrer" target="_blank">f.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://g.gtld-servers.net" rel="noreferrer" target="_blank">g.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://h.gtld-servers.net" rel="noreferrer" target="_blank">h.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://i.gtld-servers.net" rel="noreferrer" target="_blank">i.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://j.gtld-servers.net" rel="noreferrer" target="_blank">j.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://k.gtld-servers.net" rel="noreferrer" target="_blank">k.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://l.gtld-servers.net" rel="noreferrer" target="_blank">l.gtld-servers.net</a>.<br>
> net. 172800 IN NS <a href="http://m.gtld-servers.net" rel="noreferrer" target="_blank">m.gtld-servers.net</a>.<br>
> net. 86400 IN DS 35886 8 2<br>
7862B27F5F516EBE19680444D4CE5E762981931842C465F00236401D 8BD973EE<br>
> net. 86400 IN RRSIG DS 8 1 86400<br>
20190425050000 20190412040000 25266 .<br>
Uk5bsrr1dgoBFUYfzSYTi6D+QXow1CZglnE3BUZ7I/I0HjuywiSf2YLx<br>
eU1crjlYOJQdYPxDFQIH5/aItTtrM7wgvTOhfhHPHQuAj2f8ovYIlwCt<br>
hguq+9jcNTMAzrUXvi6Tb8oTb36lprYIfg21yO1d8RO6cx3L0dJMcuez<br>
WN2kxNAg+wrx+dWbOexFO7Hs0gzDPpsMx0lEOkJHcfyb/V71AnMV+nob<br>
48G/azRzQ2fJfs849OyYmjTXA88bAcxxz3kNCoddOfWuMU+WKV5Lfy7J<br>
NkegEfRCzRZYYKiDMwI0zURTg+CdZAYKuxvJQW9ddzSiK5UnYXZVSO1d fPXfYQ==<br>
> ;; Received 1168 bytes from 198.97.190.53#53(<a href="http://h.root-servers.net" rel="noreferrer" target="_blank">h.root-servers.net</a>) in 19 <br>
> ms<br>
> <br>
> <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 172800 IN NS <a href="http://dns101.comcast.net" rel="noreferrer" target="_blank">dns101.comcast.net</a>.<br>
> <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 172800 IN NS <a href="http://dns102.comcast.net" rel="noreferrer" target="_blank">dns102.comcast.net</a>.<br>
> <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 172800 IN NS <a href="http://dns103.comcast.net" rel="noreferrer" target="_blank">dns103.comcast.net</a>.<br>
> <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 172800 IN NS <a href="http://dns104.comcast.net" rel="noreferrer" target="_blank">dns104.comcast.net</a>.<br>
> <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 172800 IN NS <a href="http://dns105.comcast.net" rel="noreferrer" target="_blank">dns105.comcast.net</a>.<br>
> <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 86400 IN DS 40909 5 2<br>
30C0F50E68DCC9A2F279A994C07CF22CED97AADF44C2B1FE38A1B32B A1A34174<br>
> <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 86400 IN DS 40909 5 1<br>
DDC19733884EE533B35B4B57717BEA9B0EF2C4D1<br>
> <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 86400 IN RRSIG DS 8 2 86400<br>
20190417054136 20190410043136 51638 net.<br>
l2Vj2W+qzAziqzcC+Y+t4+6b6ADTwyILCzbySVmj5mj5J9vscR4mYf+f<br>
XzNGKen73GecLw+HiwwSzUG8jYkGtvNOMrj9ZbC4v+XWuq0EFcxDEhbJ<br>
yTAq2wPMGD6evSUSDLfqYu8hoJH9svqS06KlBjWkKQqx8X+ZIIqmUMVk ivk=<br>
> ;; Received 612 bytes from 192.42.93.30#53(<a href="http://g.gtld-servers.net" rel="noreferrer" target="_blank">g.gtld-servers.net</a>) in <br>
> 25090 ms<br>
> <br>
> <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 30 IN A 69.252.80.75<br>
> <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>. 30 IN RRSIG A 5 2 30 20190418174157<br>
20190411143657 26550 <a href="http://comcast.net" rel="noreferrer" target="_blank">comcast.net</a>.<br>
YegwZlzjBoJ+b9nWTHwRZQbce619UcOVdo6FUPG056Sod4MEchv/GCHu<br>
7BpREAUm0CBoE4qbipTiS47wIk7QJYzz10B78wRgMGNwMTUXQ571YRyq<br>
P0I3I0Dzag28j607walJOZms3lAXDzSnyvv9wocaH2MJ7Z3j68Qf5pKh YpM=<br>
> ;; Received 227 bytes from 69.252.250.103#53(<a href="http://dns101.comcast.net" rel="noreferrer" target="_blank">dns101.comcast.net</a>) in 14 <br>
> ms<br>
> <br>
> _______________________________________________<br>
> Please visit <a href="https://lists.isc.org/mailman/listinfo/bind-users" rel="noreferrer" target="_blank">https://lists.isc.org/mailman/listinfo/bind-users</a> to <br>
> unsubscribe from this list<br>
> <br>
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<br>
--<br>
Mark Andrews, ISC<br>
1 Seymour St., Dundas Valley, NSW 2117, Australia<br>
PHONE: +61 2 9871 4742 INTERNET: <a href="mailto:marka@isc.org" target="_blank">marka@isc.org</a><br>
<br></blockquote><div><br></div><div><br></div><div>I get 57ms max for the various gtld servers. Could you try this:</div><div><br></div><div>for x in a b c d e f g h i j k l m; do echo "==== $x ===="; dig <a href="http://comcast.net">comcast.net</a>. +norec +noall +auth +stats @$<a href="http://x.gtld-servers.net">x.gtld-servers.net</a>.; done<br></div><div><br></div><div>-- </div><div>Bob Harold</div><div> </div></div></div></div></div>