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Downtime notification while site is up

I’m getting downtime notification since yesterday but when checking the site is still up. I haven’t made any changes on the site for quite sometimes and the issue has just started.

Also contacted hosting, they said there’s no downtime from their server.

Wed, 31 Oct 2018 5:16:45
  • Adam
    • Support Gorilla

    Hello Andrew Kezeli

    I hope you’re well today!

    The Uptime monitor is making a request to your site (just like browser would) a number of times during a day. It’s fetching HTTP headers (it’s not a simple “ping”:wink: so apart from site being “really down” there are also other possible cases when it might report it as being down:

    1. If a site responds with a HTTP status different than 200 or 30x

    These are typical and valid responses, meaning that site is avaialble. 30x would be redirects but still they mean that site “is alive”. But if a response is different it usually means that either it’s really down or the connection is blocked, in both cases it would be considered as down.

    2. If a response time is too long

    The site might be up and running but it might temporarily be too slow. This often happens due to e.g. temporary huge spikes of traffic, some processes in background that slow it down etc. If there’s no proper response in 20-30 seconds, then even if the site actually does load in the end, it’s considered down.

    3. The server is blocking requests from Uptime, either permanently or temporarily.

    In this case, if it is, blocking, I’d say it would be temporarily. But it’s a common issue too: Uptime monitor is doing a lot of requests to the site and as a result some servers automatically detect that and temporarily block at some point. Thus, when the request is blocked, Uptime monitor cannot contact the site and considers it down. So, it marks it as downtime and starts requesting the site even more (in order to detect that it’s back-up as soon as possible) but since there’s more requests the server is still blocking it.

    This are common issues and are the reason for site being reported as down (while it’s not really down) in 99% of similar cases. I realize that your host came up with a response that there was no server outages and I believe this is absolutely true.

    However, I’d suggest getting in touch with them and asking them for two more things:

    1. if they could check logs to see if there was no unusual server resource consumption around the times when the downtimes were detected

    2. if they got any kind of firewall or anything that could possibly permanently or temporarily ban external requests due to high traffic, these IPs should be permanently white-listed for Uptime monitoring

    34.196.51.17
    
52.57.5.20

    and it would also be good to white-list additional once to make sure that no other connectivity issues to our Api occurs:

    66.135.60.59
    
66.135.49.214
    
66.135.60.64
    
104.236.238.22
    
104.236.50.140

    Kind regards,

    Adam