This article explains why the [DAEMON-4-RPD_KRT_KERNEL_BAD_ROUTE: KRT Ifstate: lost ifl for route (null)] message keeps displaying on the Backup RE SysLog.
DAEMON-4-RPD_KRT_KERNEL_BAD_ROUTE is a warning message logged each time the routing protocol process is not able to process a route obtained from the kernel. A change in Junos 12.2 caused this harmless message to be displayed unnecessarily. Before Junos 12.2, this message would be displayed only for RPD aware interfaces (that is, L3 interfaces); consequently, the message would be seen very rarely in relation to a real issue. However, after Junos 12.2, the RPD process on the backup RE started to read all nexthops, including the L2 nexthops, which are not created by RPD. Thus, RPD merely reads these L2 nexthops, discards them, and displays the message.
The RPD process on the backup RE unnecessarily reads L2 nexthops (which are not created by RPD), subsequently discards them, and displays the DAEMON-4-RPD_KRT_KERNEL_BAD_ROUTE message.
A software fix in Junos 13.3R2 and later releases was implemented to print DAEMON-4-RPD_KRT_KERNEL_BAD_ROUTE messages only for L3 nexthops (that is, RPD-created nexthops). With the fix, the messages should not be displayed for L2 nexthops (that is, non-RPD created nexthops, such as members of AE or IRB bundle). Hence, DAEMON-4-RPD_KRT_KERNEL_BAD_ROUTE messages will not be unnecessarily displayed on the backup RE.
Workaround: A possible workaround is to exclude the DAEMON-4-RPD_KRT_KERNEL_BAD_ROUTE message from the syslog file using the match command, as in the following example:
system {
syslog {
file messages {
match "!(.*RPD_KRT_KERNEL_BAD_ROUTE.*)";
}
}
}