I have just moved a host from a network that supports static IPv4 and IPv6. The IPv4 addr is set in ifcfg-eth0, and the IPv6 via RA (I set the MAC so I get an IPv6 addr that I like). I just moved the host to a network that supports static IPv4, but only dymanic IPv6, so at this time (until I get static IPv6), I need to disable the global IPv6 addressing. So in the ifcfg-eth0 file I set: IPV6INIT="no" But I am still getting a global IPv6 (and of course local scope). What else do I need to do to disable the listening for RA announcements and setting an IPv6 global address? I do not want to reboot the box. I can restart the network as needed. I seem to recall, once upon atime an option in /etc/sysconfig/network thanks
>IPV6INIT="no" > >But I am still getting a global IPv6 (and of course local scope). > >What else do I need to do to disable the listening for RA announcements > >and setting an IPv6 global address? I do not want to reboot the box.There are other modules, most notably bonding that rely on the ipv6 module being loaded. What I do is place "options ipv6 disable=1" in "/etc/modprobe.d/ipv6.conf". That does require a reboot, which I know you are looking to avoid, so you may want to try other methods to remove your address in the running configuration. Barry
On 03/06/2015 10:40 AM, Robert Moskowitz wrote:> I have just moved a host from a network that supports static IPv4 and > IPv6. The IPv4 addr is set in ifcfg-eth0, and the IPv6 via RA (I set > the MAC so I get an IPv6 addr that I like). > > I just moved the host to a network that supports static IPv4, but only > dymanic IPv6, so at this time (until I get static IPv6), I need to > disable the global IPv6 addressing. So in the ifcfg-eth0 file I set: > > IPV6INIT="no" > > But I am still getting a global IPv6 (and of course local scope). > > What else do I need to do to disable the listening for RA > announcements and setting an IPv6 global address? I do not want to > reboot the box. I can restart the network as needed. > > I seem to recall, once upon atime an option in /etc/sysconfig/network > > thanksAFAIK/recall none of the ipv6 disabling in the /etc/sysconfig files has ever quite worked the way it was advertised, I ended up writing a small shell script to be executed on startup to handle the issue. something like: echo "disable ipv6 on physical interfaces" for i in /proc/sys/net/ipv6/conf/eth* do echo 1 > $i/disable_ipv6 done but you may have better luck. -- public gpg key id: AE60F64C
On 03/06/2015 10:55 AM, Barry Brimer wrote:> > >> IPV6INIT="no" >> >> But I am still getting a global IPv6 (and of course local scope). >> >> What else do I need to do to disable the listening for RA announcements >> >> and setting an IPv6 global address? I do not want to reboot the box. > There are other modules, most notably bonding that rely on the ipv6 module being loaded. What I do is place "options ipv6 disable=1" in "/etc/modprobe.d/ipv6.conf". That does require a reboot, which I know you are looking to avoid, so you may want to try other methods to remove your address in the running configuration.'All' I need is for the system not to have a global IPv6 address. Then it will not try to connect to other global IPv6 systems which will reject the connection, as the IPv6 rDNS cannot be set, given it is a dynamic IPv6 assigned address from the ISP.
On 03/06/2015 10:59 AM, zep wrote:> > On 03/06/2015 10:40 AM, Robert Moskowitz wrote: >> I have just moved a host from a network that supports static IPv4 and >> IPv6. The IPv4 addr is set in ifcfg-eth0, and the IPv6 via RA (I set >> the MAC so I get an IPv6 addr that I like). >> >> I just moved the host to a network that supports static IPv4, but only >> dymanic IPv6, so at this time (until I get static IPv6), I need to >> disable the global IPv6 addressing. So in the ifcfg-eth0 file I set: >> >> IPV6INIT="no" >> >> But I am still getting a global IPv6 (and of course local scope). >> >> What else do I need to do to disable the listening for RA >> announcements and setting an IPv6 global address? I do not want to >> reboot the box. I can restart the network as needed. >> >> I seem to recall, once upon atime an option in /etc/sysconfig/network >> >> thanks > AFAIK/recall none of the ipv6 disabling in the /etc/sysconfig files has > ever quite worked the way it was advertised, I ended up writing a small > shell script to be executed on startup to handle the issue. something like: > echo "disable ipv6 on physical interfaces" > for i in /proc/sys/net/ipv6/conf/eth* > do echo 1 > $i/disable_ipv6 > done > > but you may have better luck. >I ended up simply disabling IPv6 for postfix. If it does not send with IPv6, no MTAs will fail to accept an IPv6 connection with no DNS or rDNS for that address. And really it SHOULD be that only postfix would be starting an outbound connection. Well there is spamassasin and clamav, but I don't believe they verify the source IP address asking for updates.