Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Home network, Cisco ASA 5505 9.0(1), Windows Server 2008 R2 (actually SBS 2011), various Mac, Windows and embedded clients. ISP is Rochester, NY Road Runner.

Often (2-3x per day) my embedded devices like SmartTV or BluRay player will not be able to access the Internet. Occasionally (not as often) it will be even more widespread and affect all devices - laptops included. Either way, when this occurs, I can log into the ASDM interface on my firewall and click renew DHCP on the outside interface and all connectivity is restored.

Troubleshooting steps, all with no improvement:

  • Recently added more RAM to F/W, increasing from 256MB to 1GB.
  • Upgraded to ASA 9.0(1) from 8.3. No difference
  • Changed blu-ray player. No difference

I've checked from the outside, and I still have a valid IP address, even before I renew. The firewall reports a valid IP. Some, but not all, devices are still working fine. But for some reason, clicking that Renew DHCP Lease on the external interface is instant relief.

Any ideas? Thanks!

share|improve this question
This is your ISP's problem. Contact their support. (I suppose it could be a problem with your Cisco device, but that's a pretty nice box so I doubt it.) – Tanner Faulkner Feb 18 '13 at 18:34
@Tanner, it could be dizziness on the router's part too. If OP is able to "see" the neighbors, but nothing outside (by IP address), it's the ISP; if not, the router got confused somehow. Perhaps a software update/upgrade of that box is in order? – vonbrand Feb 19 '13 at 3:43

Sounds like a licensing issue on the Cisco side. How many inside hosts are you licensed for? Once you have reached your limit you will not be able to access the internet for subsequent hosts. If you run a sh ver it will show how many inside hosts are licensed. Do a sh local-host and it will show you how many you are currently using. Clearing the xlates (renewing the IP) or rebooting the firewall will just let the first devices connect until you reach your limit.

share|improve this answer

It's an issue with how the ASA operates as a DHCP client. It's stucked with the DHCP lease until it times out. It's nothing to do with licenses, memory etc. It's no use to unconnect and reconnect the ethernet cable.

So is it a security feature to not manipulate the DHCP lease, or is it an anoying implementation of the DHCP client. And how to fix? I'm working on it.

share|improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .