SmartCrawl failed crawling

After setting a firewall on my server SmartCrawl is having issue crawling the site. Tried to whitelist the following IPs but still getting this error: "There was an error crawling, we weren't able to get meaningful results"

66.135.60.59
66.135.49.214
66.135.60.64
104.236.238.22
104.236.50.140

Is there any other IP specific to SmartCrawl I need to whitelist?