timeouts on http connects outbound

To: <misc@...>
Date: Friday, April 18, 2008 - 9:39 pm

Hi all,

Recently I moved from freebsd 6 to openbsd 4.2 but have had some problems.

I get a lot of timeouts on web pages with a high number of hops and I think
it may be something to do with either pf and/or sysctl.

Any help in diagnosing these timeouts much appreciated.

(box is soekris net5501 with three internal lans nat'd outbound.)
------------------------------------------------------------------------------------

sysctl -w net.inet.ip.forwarding=1
sysctl -w net.inet.tcp.mssdflt=1452
sysctl -w net.inet.tcp.recvspace=131072
sysctl -w net.inet.tcp.sendspace=131072
sysctl -w net.inet.udp.recvspace=139264
sysctl -w net.inet.udp.sendspace=32768

----------------------------------------------------------
# $OpenBSD: pf.conf,v 1.28 2004/04/29 21:03:09 frantzen Exp $
#
# See pf.conf(5) and /usr/share/pf for syntax and examples.
# Remember to set net.inet.ip.forwarding=1 and/or net.inet6.ip6.forwarding=1
# in /etc/sysctl.conf if packets are to be forwarded between interfaces.

ext_if="pppoe0"
int_if1="vr1"
int_if2="vr2"
int_if3="vr3"
out_net="192.168.11.0/16"

# Private networks, we are going to block incoming traffic from them
priv_nets = "{ 127.0.0.0/8, 192.168.0.0/16, 172.16.0.0/12, 10.0.0.0/8 }"

netbios_ports = "{ 135, 137, 138, 139, 445, 1433 }"
#table <spamd> persist
#table <spamd-white> persist

set block-policy return

scrub in all

nat on $ext_if from $int_if1:network to any -> ($ext_if)
nat on $ext_if from $int_if2:network to any -> ($ext_if)
nat on $ext_if from $int_if3:network to any -> ($ext_if)

#
block all

# block incoming traffic from private networks on external interface
block drop in quick on $ext_if from $priv_nets to any

# block outgoing traffic to private networks on external interface
block drop out quick on $ext_if from any to $priv_nets

block in quick on $ext_if inet proto tcp from any to any flags FUP/FUP
block in quick on $ext_if inet proto tcp from any to any flags SF/SFRA
block in quick o...

To: <misc@...>
Date: Saturday, April 19, 2008 - 2:23 am

You might have an MTU/MSS issue. man 4 pppoe and see if this