First Post on WebmasterWorld - so treat me gentley.
On WMT>Crawl>Crawl Errors I have a green tick for DNS, Server Connectivity and Robots.txt Fetch however when hover mouse over the Green Ticks I get these messages.
DNS - Couldn't communicate with the DNS Server
Server Conn. - Request timed out or site is blocking Google
Robots.txt - Crawl postponed because robots.txt was inaccessible
Google crawls the site about 10 times a minute from 18.104.22.168 so no access issues.Crawl stats show Pages crawled per day at 20,000
Fetch as Google works fine and Robots.txt file text in Blocked URLs works fine.
Sitemap works fine.
Only idea I have is that Google is using a new/different url to do the 'Green Tick' checking and that it is blocked in the hardware firewall.
Checked all the Google IPs I know (see below) and not blocked by ip ranges in firewall.
22.214.171.124 - 126.96.36.199
188.8.131.52 - 184.108.40.206
220.127.116.11 - 18.104.22.168
22.214.171.124 - 126.96.36.199
188.8.131.52 - 184.108.40.206
220.127.116.11 - 18.104.22.168
22.214.171.124 - 126.96.36.199
Any help gratefully received.