Might want to tweak the "setup ip6tables" logic to check first to see if any rules were in place?
On Jul 30, 2012, at 7:44 AM, Hugo Trippaers wrote: Hey Chip, Interesting, which version are you using? My box: Linux XXXXXX 2.6.32.12-0.7.1.xs6.0.2.542.170665xen #1 SMP Tue Jan 17 15:14:24 EST 2012 i686 i686 i386 GNU/Linux [root@XXXXX ~]# cat /etc/redhat-release XenServer release 6.0.2-53456p (xenenterprise) [root@XXXXX ~]# ls /proc/sys/net/ipv6/conf/all/autoconf /proc/sys/net/ipv6/conf/all/autoconf [root@XXXXX ~]# cat /proc/sys/net/ipv6/conf/all/autoconf 1 Btw I plan to add this to setupxenserver.sh: # setup ip6tables if [ -x "/sbin/ip6tables" ] ; then /sbin/ip6tables -P INPUT DROP /sbin/ip6tables -P OUTPUT DROP /sbin/ip6tables -P FORWARD DROP if [ -x "/etc/init.d/ip6tables" ] ; then /etc/init.d/ip6tables save fi fi # disable IPv6 if [ -d "/proc/sys/net/ipv6/conf/all" ] ; then /sbin/sysctl -w net.ipv6.conf.all.forwarding=0 /sbin/sysctl -w net.ipv6.conf.all.accept_ra=0 /sbin/sysctl -w net.ipv6.conf.all.accept_redirects=0 /sbin/sysctl -w net.ipv6.conf.all.autoconf=0 /sbin/sysctl -w net.ipv6.conf.all.disable_ipv6=1 fi Cheers, Hugo -----Original Message----- From: Chip Childers [mailto:chip.child...@sungard.com] Sent: Monday, July 30, 2012 4:06 PM To: <cloudstack-dev@incubator.apache.org<mailto:cloudstack-dev@incubator.apache.org>> Subject: Re: Disable IPv6 for systemvm The latest Xen Server install seems to have IPv6 disabled (just checked in my lab). Is it enabled in XCP? (I may be showing my Xen ignorance here) - chip On Jul 30, 2012, at 9:24 AM, Hugo Trippaers <htrippa...@schubergphilis.com<mailto:htrippa...@schubergphilis.com>> wrote: Hey Chip, Yeah, I want help :-) I just committed the sysctl.conf changes for the systemvm. This morning i applied them to my test environment and they do the job. We could add the actual sysctl command to the vmops next to adding the IPv6 ip6tables statements I think. Cheers, Hugo -----Original Message----- From: Chip Childers [mailto:chip.child...@sungard.com] Sent: Monday, July 30, 2012 3:13 PM To: cloudstack-dev@incubator.apache.org<mailto:cloudstack-dev@incubator.apache.org> Subject: Re: Disable IPv6 for systemvm On Mon, Jul 30, 2012 at 7:32 AM, Hugo Trippaers <htrippa...@schubergphilis.com<mailto:htrippa...@schubergphilis.com>> wrote: By the way, we might want to add the same configuration to vmops for XenServer. Currently it is possible to have a tenant vm send a router advertisement on the isolated lan that is picked up by XenServer. Even though XenServer only has a bridge interface in the tenant lan that interface will be autoconfigured. A simple ping to the local all-node address (ff02::1) will tell you the mac off of the XenServer interface. As XenServer has ssh active on all interfaces you can directly connect to the ssh daemon on the XenServer. We only push a IPv4 firewall to the XenServer so the IPv6 firewall is default (ACCEPT everything). Still you only gain access to the ssh port, but that is something that should not be possible from a tenant lan. Cheers, Hugo As a provider, this one is even more concerning. Unless someone has an objection, I'd agree with your solution. We can remove a DENY rule in the future, after IPv6 support is added properly / completely. If you want help working up the fix for this, please let me know! -chip Stratosec<http://stratosec.co> - Secure Infrastructure as a Service o: 415.315.9385 @johnlkinsella<http://twitter.com/johnlkinsella>