apache 2.2 - ERR_CONNECTION_TIMED_OUT after GCP instance resize?

So I'm totally at a loss for what's going on here. I logged into my GCP instance the other day to see that it was prompting me to upgrade the size of my instance. The instance was hosting 4 low traffic wordpress sites on a micro instance, so fair enough, I went ahead and upgraded it to a small instance.

The system took my server offline for about 2 minutes, resized the instance, and then booted it back up. However now post reboot non of my sites are reachable giving me a dreaded ERR_CONNECTION_TIMED_OUT.

I'm gone through the apache2 error logs, but this is the only clue that in here which doesn't seem like something that should totally be bringing down the instance:

[Sun Jul 02 06:29:59.116350 2017] [mpm_prefork:notice] [pid 1854] AH00163: Apache/2.4.10 (Debian) configured -- res
uming normal operations

[Sun Jul 02 06:29:59.116399 2017] [core:notice] [pid 1854] AH00094: Command line: '/usr/sbin/apache2'

[Sun Jul 02 20:54:19.098816 2017] [:error] [pid 17958] [client 179.219.113.226:60741] script '/var/www/argineconsul
ting.com/public_html/command.php' not found or unable to stat

[Mon Jul 03 02:33:51.193230 2017] [mpm_prefork:notice] [pid 844] AH00163: Apache/2.4.10 (Debian) configured -- resu
ming normal operations

[Mon Jul 03 02:33:51.225527 2017] [core:notice] [pid 844] AH00094: Command line: '/usr/sbin/apache2'

[Mon Jul 03 02:48:01.236769 2017] [mpm_prefork:notice] [pid 844] AH00169: caught SIGTERM, shutting down

[Mon Jul 03 02:48:02.309718 2017] [mpm_prefork:notice] [pid 1441] AH00163: Apache/2.4.10 (Debian) configured -- res
uming normal operations

[Mon Jul 03 02:48:02.309788 2017] [core:notice] [pid 1441] AH00094: Command line: '/usr/sbin/apache2'

I've tried going back through the setup for my VPS to make sure everything is working there - nothing seems out of wack. Any thoughts appreciated.

Answer

I figured this out - apparently when you resize an instance on GCP it issues you a new IP address. I had to update Cloud DNS with the new IP addresses and everything worked fine. I think the resize process should have expressly called this out because I wasted a number of hours trying to figure out what was wrong. :-(