Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations strongm on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

No outgoing connections with DSL-HS-2.3MBS 1

Status
Not open for further replies.
Jun 20, 2002
52
US
Hi,

I have a client who has been using DSL-HS-2.3MBS for quite a while with no problems.

Recently he started having a problem which manifests itself like that.
1. Everything works great anywhere from several hours to several days.
2. Just of a sudden no outgoing connections can be initiated. No pings, no anything. Router cannot ping the DSLAM. DSLAM can ping the router just fine.
3. Incoming connections still go through with some initial delay at the time connection gets established. After that connection works flawlesly for practically unlimited time.
4. Initial telnet connection into the router on the LAN side is significantly delayed at that time also. After being established works flawlessly.

I looked into all available "show" statistics at the time it happens. Nothing abnormal.

My theory is that NAT gets overflown. It is just a theory, I did not find any way to look into the router memory or otherwise troubleshoot this area.

Did anybody run into a similar problems? Any troubleshooting ideas?

So far I have replaced the router with the new one only to experience the same problem in a couple days.

Thank you,
Vladimir Mikhelson
 
Hi,

I don't have the same problem, but I found this at Lucent.com:

Run NAPT from the diagnostics. Verify that the size is maxed out to 500 or rapidly increasing. The NAT table is reset to zero every time it reconnects to the internet. Most commonly we see the NAT table maxed out on nailed connections. Also, when we observe the NAT table we can find the source of the NAT table entry and the port, see the protocol and the time to time out for the NAT table entry. What happens is when a response in not returned from the internet for a route request from the private ip source, the NAT table needs to wait till it times out before the NAT table entry is removed. Solutions are
1. To remove the source of the guilty packet.
2. Set up a filter to prevent the need to route to the internet the guilty packets.
3. Periodically reset the nailed connection to reset the NAT table to zero. Do this by simply going to the connection profile and hang up connection (ctrl-D and select 2). The nailed connection will subsequently restore itself and the nat table will be reset to zero.

Maybe you could use it.

Regards,
Frank
 
Hi Frank,

Thank you very much. It looks exactly like what I was looking for.

Can you please send a link to the Lucent document? Do they have more unlisted commands?

Thank you,
Vladimir
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top