I have a site which had experienced a change in IP address from shared IP to static IP over 2 months ago. The physical server and nameservers for the domain remained the same. The change was only in shared IP to static IP. I am seeing a strange behavior on the spidering pattern of googlebot with its different IPs. The bot with IPs 6x.xxx.xxx.xxx spiders the site correctly at the current static IP address. However the bot with IPs 216.xxx.xxx.xxx is spidering the site at old IP address which was a shared IP(so it is accessing the main cobalt raq server page and getting a bunch of File Not Found pages). The site in question was a year old and ever since the IP change 2 months ago on May 4th, one month google indexed the main cobalt raq page as our home page with high PR and in this month update it removed the entire site. Not sure what it is going to do next month!. My question would be why the bots are so confused about a mere small change in IP address of a domain from shared to static IP?. And what could I possibly do to correct this behavior and see my site is indexed back correctly!
yankee, this domain does not have fresh date but in the past all the content got regularly spidered every month and indexed. since the IP change, the spidering is very limited to a few pages and as i said in the current update the site was fully wiped out(with no PR, greyed out PR and not PR0) and the prior update had about 200 pages indexed with home page as the server default page 'welcome to cobalt raq' with a high PR. i believe different bots reconcile their findings and due to the differences (as one spidered the correct site address and another spidered the old server IP cobalt raq home page) in what different bots found - they skip the site from being indexed. i am not sure if this is making the bot think we are cloaking as one bot gets cobalt raq page or file not found pages and the other gets correct pages. if so, i hope google syncs up their DNS cache for different bot IPs before throwing out a site in the water:).