Internet access through T1 line down after replacing hardware firewall
Posted on 2007-03-28
I need help with this potential employment question. This is NOT an exam question, but part of a long list for me to research and get back within the next week:
"Your company has an internet connection supplied to the LAN from a hardware firewall connected to a T1 router. During normal business hours the Internet goes down. After checking the T1 router and the corporate firewall you find that the firewall has suffered a hardware failure. You replace the hardware firewall with a spare firewall. The spare firewall is the exact same model and runs the same firmware. You use the configuration file that was in production on the failed firewall. The configuration file is sound. You shutdown the old firewall and remove it from the network and you install the new firewall with the same configuration file already in place. You cable the firewall properly and it starts normally. None of the systems on your network can get out to the Internet. What is the highest probable cause for this issue and what do you do first to resolve the issue. Also list other probable causes for the Internet connectivity issue."
My initial thinking is that the new hardware firewall, although identical in model, firmware, and configuration file, has a different MAC address, and there may be an issue with the T1 provider's router and this new address. Secondly, could installing the firewall with the configuration file already in place be an issue, as opposed to running the configuration file after physically installing the hardware firewall?
Thanks in advance for any leads on this.