Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

Cannot ping segment from CUCM

Hi all,

I'm implementing CUCM in a customer, their segment ip address is rather weird which is I cannot ping that segmet from CUCM and if i traceroute the packet is bound back to CUCM.

It is hard to change the segment ip address because too many PC with that segment ip address. Is there any way to make CUCM can ping segment


Everyone's tags (1)
New Member

Re: Cannot ping segment from CUCM

That is not a legal private IP address range according to RFC1918 so they should not really be using it.

169.254/16 addresses are reserved for link local addressing (RFC 3927) - this is what a machine would assign itself should it be configured for DHCP and not receive an offer.

Given that their 169.254 segment is operational and working okay, I would go through standard troubleshooting techniques through the OSI layers:

1. check physical connectivity

2. check arp/mac address table entires are correct on switches and end hosts

3. check ip addressing of end hosts are on the same layer 3 vlan with no filtering/access control, with correct default gateways

4. check for any host-based access control - software firewalls etc.

If you could send printouts of arp tables, mac tables, routing tables and ip addressing configuration of some example hosts that would be useful.

Hope this helps, Ash.