UDP ok but TCP delayed

[Ian Smith]

Re: freebsd-questions Digest, Vol 160, Issue 13
 > Message: 29
 > Date: Thu, 11 Jan 2007 00:24:03 -0500
 > From: Bob McIsaac <bobmc at bobmc.net>

 > Got helpful replies before but still have a mystery 10 second delay
 > on a TCP connection. Slashdot takes with all it's links takes about
 > 30 seconds to load in any browser.  One tiny email displays a 10sec
 > progress bar.  Yet ping, FTP,  or pkg_add seems normal.  I get the
 > same result on 2 different computers. Both work fine with Linux.
 > 
 > My interest in FreeBSD is as an alternative for embedded projects
 > where Linux would typically be an automatic choice.
 > 
 > I confirmed with tcpdump that my ISP nameserver replies with
 > an IP address and nothing happens for 10 seconds until my
 > browser makes the connection.

I responded in some detail before re your tcpdump.  It clearly showed
that the nameserver you were using at 192.168.1.254 was *failing* to
respond to 1) AAAA queries and 2) queries for its own reverse address.

 > tcp_keepalive="NO"

The default is YES .. any particular reason for using NO?

 > ifconfig_vr0="DHCP"
 > hostname="buffy.feline.cat"

 > # -- /etc/resolv.conf ---
 > nameserver 192.168.1.254
 > 
 > # --- /etc/hosts ---
 > ::1       localhost.home.com localhost
 > 127.0.0.1  localhost.home.com localhost
 > 127.0.0.1  buffy.feline.cat buffy

Hmm.  Maybe remove the IPv6 entry, you said you weren't using IPv6 but
the tcpdump did show your box amaking AAAA queries.

I'm still curious as to where 192.168.1.254 lives?  In most cases this
would be your local ADSL router, say.  It doesn't *look* like it'd be
the address of your upstream provider's DNS, but then there are some
funny ISPs out there I guess.

Is 192.168.1.254 also your defaultrouter?  It's not in your rc.conf, but
perhaps that's being assigned by DHCP?  So should be, perhaps, upstream
DNS server address/es?  If 192.168.1.254 is local, it's misconfigured.

I *still* must suggest putting the address/es of known good upstream
nameservers in /etc/resolv.conf to see if that doesn't deal with your
delay, which seems almost certainly a DNS issue from everything you've
posted so far.

If that doesn't help, show us 'netstat -finet -ra' and 'ifconfig'?

Cheers, Ian

(please cc me; getting the next digest can take up to half a day)