Google Analytics: Real Time works, historical data does not
<p>This morning one of my websites had an unexpectedly large increase in traffic which overwhelmed our VPS. I asked our hosting company to temporarily double our CPU and RAM to cope with the increased load and the website came back online and has been working fine ever since, except Google Analytics has stopped reporting data (Events, Sessions, everything) and shows zero from the 6am onwards which is around when we had the server issues. However, Real Time reporting still works and even AdWords reports 3 times as many clicks to our site as is reported in GA. I am thinking this may be a glitch because I know there can be a delay in reporting historical data but I just wanted to get some opinions here in case there is something obvious that I have overlooked which is preventing data from being recorded. </p>

<p><strong>Here is a summary of what I know and have checked:</strong></p>

<ol>
<li>Real Time reporting is working.</li>
<li>GA reports no problems with tracking code, neither does tag manager.</li>
<li>We haven't changed any code and nothing has changed on the server apart from increased resources (CPU and RAM).</li>
<li>A subdomain on the same server with a different GA account is reporting fine, although this site has only a tiny fraction of the traffic on our main site.</li>
<li>I am not using a filtered view (and I have checked I am looking at today's date!).</li>
</ol>

<p>Just to put some figures in here in case they make a difference: On a normal day we would expect around 60k visits. The last reported figure was 9.7k visits between 5-6am this morning then it has been zero ever since (this was 10 hours ago). I know from Real Time stats that we have had between 500-2000 simultaneous users on the site all day (it is reporting 500 right now) and even AdWords has reported 30k clicks but nothing is showing up in the historical data.</p>

<p>Has GA just glitched because of the sudden increase in traffic or does it sound like something I need to be investigating on this end?</p>