My hosting provider emailed me last month and said my server was lagging very bad and said that there could be a DOS attack. They blocked a bunch of IP addresses and claimed they fixed the problem. So about a month later, I notice that all of my websites are losing a lot of traffic and I can't figure out why. It wasn't until just recently that I realized that the Google crawler was blocked. I called my hosting admin and got the problem fixed, but now 500k of my pages are pulled off of Google. I resubmitted my sitemaps and hope for the best. Does anyone have any recommendations going forward? Now that the google crawler is back on my site, do I have a good chance of getting back my lost pages?
Wow that is quite a hurdle to overcome! I don't think there is much you can do other than just wait, Google will have to re-index all of those pages unfortunately and this will just take some time.