It is possible on RHEL systems to disable IPv6 autoconfiguration either system-wide (in /etc/sysconfig/network) or or specific interface (in that interface's /etc/sysconfig/network-scripts/ifcfg-* file) using the IPV6_AUTOCONF=[yes/no] statement.
I have been looking for an equivalent mechanism in SLES, so far without success. Approaches already tried include adding sysctls to /etc/sysctl, /etc/sysconfig/network/ifsysctl, and interface-specific ifsysctl files under /etc/sysconfig/network, as well as specifying these sysctls in that interface's own ifconfig file. Speicifcally, {net.ipv6.conf.all.autoconf, net.ipv6.conf.default.autoconf, net.ipv6.conf.all.accept_ra, net.ipv6.default.accept_ra} when attempting to control this behavior system-wide, and (for example) {net.ipv6.conf.eth0.autoconf and net.ipv6.conf.eth0.accept_ra} when attempting to do so on a per-interface basis. Depending on the timing of when these configuration files are read an interpreted during the boot process, however, in all cases either the attempt to apply the sysctls fails because the ipv6 kernel module hasn't yet been loaded or the relevant sysfs nodes have not yet been created, or because the sysctls are applied after the network interface has already been brought online and accepted a router advertisement and global autoconfigured IPv6 address as per its default behavior. Disabling these sysctls and then restarting the network (or a specific interface) will disable autoconfiguration for that interface, but I have not been able to do so for the first time the interface comes up after boot. Also, at least in our environment, restarting a network interface causes it to fail to re-autoconfigure itself even with all the autoconfiguration sysctls left "on" - such that the interface will not regain an autoconfigured IPv6 address until after it the Linux has been rebooted. This behavior has not been seen on our RHEL systems, so I believe it is a symptom of something happening within the operating system rather than something in our network's configuration. Has anyone on this list successfully disabled IPv6 autoconfiguration at* *boot time for a SLES system, and if so then what approach did you take to do so? Also, has anyone else seen (and/or found a way to prevent) the issue I've encountered with interfaces on SLES failing to regain their autoconfigured network addresses when they or the network service is restarted without rebooting the Linux? Thank you. - Chris ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/