| linkteo 2003-03-31, 11:32 am |
| I have a Cisco 1720 router with leased line to internet and ISDN backup to internet. The ISDN backup is using "Backup interface" method. My ISP assign different IP pool for my leased line and ISDN. So I use route-map so that the router will select appropiate pool when using leased line or ISDN.
For testing purposes, When I am connecting using leased line, I issue a continuous ping to my ISP primary DNS server, 165.21.83.88. When I remove the leased line connection, the ISDN kick in and runs fine, but my ping never recovered from "request timeout"! if I stop the ping and issue a new ping to my ISP secondary DNS server, 165.21.100.88, I got reply. when I cancel this ping and ping back 165.21.83.88, it still request timeout!
Now when I put back the leased line connection, the ISDN goes down. Now I can ping 165.21.83.88 but I cannot ping 165.21.100.88.
It seems like the NAT translation for 165.21.83.88 continuously stick to leased line although I am using ISDN backup. likewise the NAT translation for 165.21.100.88 stick to ISDN connection even though I am using leased line.
Why?? How to solve this problem?? |