After Server Migration 1 in 5 still see old site (40 hours later,new site is perfect)

[natecoupons]

We have a weird issue and it's the first time in all the times I have moved and migrated servers that this has happened. I am curious if anyone here has an idea about why this might be happening. It's been over 36 hours since we have migrated.

We migrated to a new dedicated server and the new server and the site itself works perfectly. About 70-80% of our traffic can see the site (on the new server) no problem. We get around 200,000 unique visitors so when a large amount of people can't our site can't see the site, they let us know. About 20% (simply going off who on our staff can't see) is still getting the old site. They get a standard message from vBulletin saying the site is closed for maintenance and that we are working on our servers.

The site is resolving to the correct IP.

Another point: our homepage is not vBulletin, but a Wordpress blog.

I communicate with our visitors on Facebook and some of them let me know that they don't have access. I thought this was very odd. So I have explored a couple of options with them to really no avail. Here are their comments:

OK. So I cleared the cache and browsing history and restarted to computer and everything was fine for about 30 min and then it right back to how it was. Weird too...because it's like I'm getting thrown back to before I cleared. It's hard to explain but old PM's become new again. I get the notice of them being new with the vBulletin message. You caught us during a brief maintenance window! We are actually migrating to our new servers! Sorry for the inconvenience, this won't take to long. Estimate for server migration: 2-3 hours or 3-4am EST

The homepage is blank but I can still get on using the link you provided earlier. I just don't have full access.

(We put the homepage a Wordpress blog in maintenance mode before we moved the site, so she is seeing the blank page b/c the old server and all the files are probably still in maintenance mode.

When I do a DNS cache flush I can see the blog and the homepage until I get the vBulletin message and then it's blank but I can still get to the forum using your link.

I'm still having lots of problems. I was just for about ten minutes before getting kicked out again (I get the maintenance message saying the site is down) while trying to "like" a few posts.

i have cleared my browser cache, reset my computer, deleted my cookies and still nothing

I initially thought it was the DNS cache, but I'm not sure. We do have a couple of cache plugin's on our Wordpress site. Here is a thread on a Wordpress support site about someone else who had a similar issue.

The wordpress plugins we use is related to caching are W3 Total Cache and WP Minify
WP Super Cache is deactivated but not deleted.

We WERE running litespeed, just moved back to apache.

Thoughts on this....anyone else have this issues and what would you recommend? I think two or three or five heads are better than one!!

[OldSchoolDSL]

If you're using Cloudflare DNS .... Log into your account and flush the cache

The same out apply if you're using Google Page Speed Service

48 hours later it still could be your DNS has not yet populated. Rare for it to take that long, but possible.

Worse case is the IP on your new server is black listed some place and is refusing to populate.