[RndTbl] Shaw Internet going away

Bill Reid billreid at shaw.ca
Thu Apr 19 23:16:52 CDT 2007

There have been a number of posts about the problems of Shaw Internet going 
away. It is not clear what the problem is and when Trevor and starting runing 
scripts which did pings, etc. the problem went away for me.

I was installing a new server and of course the MAC address is different. When I 
powered cycled the cable modem it still would not allow my MAC address to 
communicate. After fighting this for a while I phoned Shaw tech support. I 
having the modem reset, etc. I guess the tech went away to consult. It turns out 
that the arp cache is not updated continuously and is cleared every 4 hours. So 
a MAC IP pairing hangs around for a while. This potentially could cause the 
problems I was seeing if someone was using my IP address. It seems a bit far 
fetched but not updating the arp cache could lead to problems that correct 
themselves when the cache is clear.

My solution was to clone the old server MAC address. This will become standard 
procedure since if you want to go back to the old server you do not want to wait 
4 hours.

Of course this is really only a problem with static IPs since if you do a dhcp 
renew you should get a new IP address.

-- Bill

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