New server worked for a few hours, but now connections time out

Question

I used this guide to set up Apache2 and PHP5: link.

I set up a simple PHP script, debugged some permissions issues, got everything working. A few hours later, it stopped working. I could no longer access my script over the web.

When I open a browser on my PC and point to the server's IP address (I am not using a domain, this server is just for serving one PHP script), the connection times out. I followed several steps from this guide: link.

Here's what I've tried so far:

• Confirmed that apache is running
• Confifmed that port 80 is open
• Confirmed that html/php pages are at the proper directory

Other than installing Ubuntu, Apache, and PHP, all I have done is change a few permissions. So, since I'm new to Ubuntu, I assume that's where the problem must be. Here's how the permissions are set in my html directory:

$ pwd
/var/www/html
$ cd /var/www
$ ls -l
total 4
drwxr-xr-x 2 root root 4096 May  3 12:07 html
$ cd html
$ ls -l
total 20
-rw-r-Sr-- 1 www-data root       379 May  3 12:30 dataentry.php
-rw-r--r-- 1 www-data www-data  1383 May  3 13:03 datalog.csv
-rw-r--r-- 1 root     root     11510 May  3 10:40 index.html
$ 

Note I'm not using index.html - I just go directly to my script - so I'm assuming it doesn't matter what permissions are set for index.html.

I also checked my apache error log, and these are the last few entries from AFTER the last time I could connect:

[Tue May 03 13:20:33.630151 2016] [mpm_prefork:notice] [pid 16374] AH00169: caught SIGTERM, shutting down
[Tue May 03 13:20:34.710242 2016] [mpm_prefork:notice] [pid 17929] AH00163: Apache/2.4.7 (Ubuntu) PHP/5.5.9-1ubuntu4.16 configured -- resuming normal oper$
[Tue May 03 13:20:34.710284 2016] [core:notice] [pid 17929] AH00094: Command line: '/usr/sbin/apache2'
[Thu May 05 14:59:03.584613 2016] [mpm_prefork:notice] [pid 17929] AH00169: caught SIGTERM, shutting down
[Thu May 05 14:59:04.664584 2016] [mpm_prefork:notice] [pid 26724] AH00163: Apache/2.4.7 (Ubuntu) PHP/5.5.9-1ubuntu4.16 configured -- resuming normal oper$
[Thu May 05 14:59:04.664628 2016] [core:notice] [pid 26724] AH00094: Command line: '/usr/sbin/apache2'

Does anything here stand out? What are some other trouble-shooting steps I can take?

Answer 1

Turns out it was a firewall issue. I needed to change from this:

Chain ufw-user-input (1 references)
  pkts bytes target     prot opt in     out     source               destination         
     0     0 ACCEPT     all  --  *      *       X.X.X.X              0.0.0.0/0           
  4473  250K ACCEPT     tcp  --  *      *       0.0.0.0/0            0.0.0.0/0            tcp dpt:22
     0     0 ACCEPT     udp  --  *      *       0.0.0.0/0            0.0.0.0/0            udp dpt:22

To this:

Chain ufw-user-input (1 references)
 pkts bytes target     prot opt in     out     source               destination         
    1    52 ACCEPT     all  --  *      *       X.X.X.X              0.0.0.0/0           
    2   112 ACCEPT     tcp  --  *      *       0.0.0.0/0            0.0.0.0/0            tcp dpt:22
    0     0 ACCEPT     udp  --  *      *       0.0.0.0/0            0.0.0.0/0            udp dpt:22
    9   420 ACCEPT     tcp  --  *      *       0.0.0.0/0            0.0.0.0/0            tcp dpt:80
    0     0 ACCEPT     udp  --  *      *       0.0.0.0/0            0.0.0.0/0            udp dpt:80

Not sure why it worked for a while at first. The person in my lab who ended up helping me with this speculates that the server may have loaded some default configuration during some upgrade/reboot process.