[j-nsp] graceful switchover - "kernel-replication subsystem not running"

[Johannes Resch]

hi,

i'm currently playing with a M20 with two RE2.0 (both running the current
junOS 6.4-release), trying to enable graceful switchover.

referring to juniper docs
(http://www.juniper.net/techpubs/software/junos/junos64/swconfig64-system-basics/html/chassis-config22.html#1124679)

the relevant config (commited with "commit sync") is

user at host> show configuration chassis redundancy
routing-engine 0 master;
routing-engine 1 backup;
graceful-switchover {
    enable;
}

however, "sh system switchover" gives

{master}
user at host> show system switchover
error: the kernel-replication subsystem is not running


what else do i need to enable graceful switchover?

besides, how mature is this feature?
i'd be interested in any experiences and comments.

thanks & best regards,
-jr