Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 27 Apr 2002 16:32:28 -0400
From:      "Joe & Fhe Barbish" <barbish@a1poweruser.com>
To:        "Anton Shcherbinin" <useperl@fastmail.fm>
Cc:        "FBSDQ" <questions@FreeBSD.ORG>
Subject:   RE: 1 minute delay while connecting to any host
Message-ID:  <LPBBIGIAAKKEOEJOLEGOOEPMCOAA.barbish@a1poweruser.com>
In-Reply-To: <743669500.20020427213601@fastmail.fm>

next in thread | previous in thread | raw e-mail | index | archive | help
You left out a lot of information about your configuration, so I am taking a
shot in the dark here. Your FBSD system does not know the DNS servers to
query to convert the domains names into ip address. FBSD looks in the
/etc/resolv.conf for the ip address of your ISP DNS. This file will be
populated with the correct ip address if you tell user ppp to get and use
the isp's DNS. To make this happen automatically you have to add the
following to your /etc/ppp/ppp.conf file

 enable dns		# Gets the ISP's DNS IP address & places them
			# in resolv.conf for reference by FBSD box.

If you have this in place them you also have to allow the IPFW firewall
access to the DNS services with statements like.

 add 00660 allow tcp from any to any 53        # allow out
 add 00661 allow tcp from any 53 to any        # allow in
 add 00662 allow udp from any to any 53        # allow out
 add 00663 allow udp from any 53 to any        # allow in



-----Original Message-----
From: owner-freebsd-questions@FreeBSD.ORG
[mailto:owner-freebsd-questions@FreeBSD.ORG]On Behalf Of Anton Shcherbinin
Sent: Saturday, April 27, 2002 1:36 PM
To: freebsd-questions@freebsd.org
Subject: 1 minute delay while connecting to any host

This is my 1st post to this list, and I am completely new to FreeBSD. If
I  had better ask such questions anywhere else, please tell me the right
place for this.

I  installed  FreeBSD  4.5 Release. When my host is trying to connect to
any  other  host  specified  by  name, I experience a huge (1.5 minutes)
delay before the hosts are connected. For example, suppose I want to get
http://yahoo.com/ page. I write:

$ telnet yahoo.com 80

At  the  same time (actually, a bit earlier), I wrote at another console
as root:

# tcpdump -n

And here is tcpdump's output (a bit edited for clarity):

18:37:51.501962 my_host.1055 > our_DNS_server.53:  4486+ AAAA? yahoo.com.
(27)
18:37:56.512212 my_host.1056 > our_DNS_server.53:  4486+ AAAA? yahoo.com.
(27)
18:38:06.522353 my_host.1057 > our_DNS_server.53:  4486+ AAAA? yahoo.com.
(27)
18:38:26.532655 my_host.1058 > our_DNS_server.53:  4486+ AAAA? yahoo.com.
(27)
18:39:06.543281 my_host.1059 > our_DNS_server.53:  4487+ A? yahoo.com. (27)
18:39:06.683069 our_DNS_server.53 > my_host.1059:  4487* 2/5/5 A
66.218.71.113, (238)
18:39:06.683609 my_host.1028 > yahoo.com.80: S 2162865409:2162865409(0) win
65535 <mss 1460,nop,wscale 1,nop,nop,timestamp 579069 0> (DF) [tos 0x10]
18:39:06.909922 yahoo.com.80 > my_host.1028: S 2552035614:2552035614(0) ack
2162865410 win 65535 <mss 1460,nop,wscale 1,nop,nop,timestamp 66944899
579069>
18:39:06.909984 my_host.1028 > yahoo.com.80: . ack 1 win 33304
<nop,nop,timestamp 579091 66944899> (DF) [tos 0x10]

That  is, my host tries to resolve yahoo.com at our DNS server, *but* it
looks  for 'AAAA' RR, and not 'A'. It gets no reply, and in 5 seconds it
retries  the  query (again, 'AAAA' RR). No reply again, it retries in 10
seconds,  then  again  in  20  seconds.  No  reply  within  40  seconds.
*FINALLY*,  my  host  asks  DNS server for 'A' RR for yahoo.com . And no
wonder that in several milliseconds DNS server tells my host yahoo.com's
IP  address.  Then,  within  several milliseconds, my host and yahoo.com
become TCP-connected.

As  you  can see, I had to waste 5+10+20+40==75 seconds watching my host
try to find nonexistent AAAA resource record. And things are the same if
I try to send mail or to connect to ftp site or whatever else.

What have I done wrong? What should I do? Thanks a lot for any ideas.

I  general,  what  are AAAA records? RFC1034/1035 say nothing about such
RR. What TFM should I read about them?

--
Anton


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-questions" in the body of the message


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-questions" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?LPBBIGIAAKKEOEJOLEGOOEPMCOAA.barbish>