I'm using a firewall on the HN to open/close the ports of the containers directly from the HN. I'm using the iptables script from the openvz wiki.
Everything works fine but I cannot ssh out from the VPS. I can enter via ssh into the container, but if I try to do an ssh connection from the VPS to another server the firewall blocks it.
What rules should I add the the iptables script to allow the outgoing ssh connection? Here's the script:
#!/bin/sh
# firewall Start iptables firewall
# chkconfig: 2345 97 87
# description: Starts, stops and saves iptables firewall
# This script sets up the firewall for the INPUT chain (which is for
# the HN itself) and then processes the config files under
# /etc/firewall.d to set up additional rules in the FORWARD chain
# to allow access to containers' services.
# http://wiki.openvz.org/Setting_up_an_iptables_firewall
. /etc/init.d/functions
# the IP block allocated to this server
SEGMENT="192.168.0.0/24"
# the IP used by the hosting server itself
THISHOST="192.168.0.1"
# services that should be allowed to the HN;
# services for containers are configured in /etc/firewall.d/*
OKPORTS="53"
# hosts allowed full access through the firewall,
# to all containers and to this server
DMZS="12.34.56.78 90.123.45.67"
purge() {
echo -n "Firewall: Purging and allowing all traffic"
iptables -P OUTPUT ACCEPT
iptables -P FORWARD ACCEPT
iptables -P INPUT ACCEPT
iptables -F
success ; echo
}
setup() {
echo -n "Firewall: Setting default policies to DROP"
iptables -P INPUT DROP
iptables -P FORWARD DROP
iptables -I INPUT -j ACCEPT -m state --state ESTABLISHED,RELATED
iptables -I FORWARD -j ACCEPT -m state --state ESTABLISHED,RELATED
iptables -I INPUT -j ACCEPT -i lo
iptables -I FORWARD -j ACCEPT --source $SEGMENT
success ; echo
echo "Firewall: Allowing access to HN"
for port in $OKPORTS ; do
echo -n " port $port"
iptables -I INPUT -j ACCEPT -s $SEGMENT -d $THISHOST --protocol tcp --destination-port $port
iptables -I INPUT -j ACCEPT -s $SEGMENT -d $THISHOST --protocol udp --destination-port $port
success ; echo
done
for ip in $DMZS ; do
echo -n " DMZ $ip"
iptables -I INPUT -i eth0 -j ACCEPT -s $ip
iptables -I FORWARD -i eth0 -j ACCEPT -s $ip
success ; echo
done
CTSETUPS=`echo /etc/firewall.d/*`
if [ "$CTSETUPS" != "/etc/firewall.d/*" ] ; then
echo "Firewall: Setting up container firewalls"
for i in $CTSETUPS ; do
. $i
echo -n " $CTNAME CT$CTID"
if [ -n "$BANNED" ]; then
for source in $BANNED ; do iptables -I FORWARD -j DROP --destination $CTIP --source $source ; done
fi
if [ -n "$OPENPORTS" ]; then
for port in $OPENPORTS ; do iptables -I FORWARD -j ACCEPT --protocol tcp --destination $CTIP --destination-port $port ; done
for port in $OPENPORTS ; do iptables -I FORWARD -j ACCEPT --protocol udp --destination $CTIP --destination-port $port ; done
fi
if [ -n "$DMZS" ]; then
for source in $DMZS ; do iptables -I FORWARD -j ACCEPT --protocol tcp --destination $CTIP --source $source ; done
for source in $DMZS ; do iptables -I FORWARD -j ACCEPT --protocol udp --destination $CTIP --source $source ; done
fi
[ $? -eq 0 ] && success || failure
echo
done
fi
}
case "$1" in
start)
echo "Starting firewall..."
purge
setup
;;
stop)
echo "Stopping firewall..."
purge
;;
restart)
$0 stop
$0 start
;;
status)
iptables -n -L
;;
*)
echo "Usage: $0 <start|stop|restart|status>"
;;
esac
And this is an example of the single container configuration which gets parsed from the firewall script.
# This file is processed by /etc/init.d/firewall
CTID="1" # the container's ID#
CTNAME="Customer1" # A human-friendly label for the container
CTIP="192.168.1.34" # the IP address for this container
OPENPORTS="80 443 22" # ports that should be universally opened
# to the entire Internet
DMZS="1.2.3.0/24 5.6.7.8/32" # IPs and blocks that should have full access
# to the container's services
BANNED="" # IPs and blocks that should be entirely
# blocked from the container's services
