Seems like SwOS have some problems with ARP replies. You can add static ARP entries for your switches on the Dude server to confirm.

I have the same problem but we monitor with nagios. is there a fix for this problem

Same thing here... 2 managed switches on a management vlan over a vpn behind an rb450g. Dlink 24port, can ping, ssh, and get to webui. RB250gs, can get to webui, but ping replies get dropped in the firewall... All rules are right, but it just wont reply.

Probably something to do with not being able to define a gateway or netmask. The management subnet at this site is a /29...

I have the same problem when monitoring with nagios. come on MT

has this problem ever been resolved ?