Lock Screen MAC OS X Sierra

This is great! Finally a key combination to lock screen of Mac OS X - Sierra:

Command + Control + Q

Apache HTTPD Log Time to serve request in seconds

You just need to add %T

An example of Log Format below:

LogFormat "%h %l %u %t \"%r\" %>s %b %T \"%{Referer}i\" \"%{User-Agent}i\" \"%{X-Forwarded-For}i\" \"%{SN-Akamai-IP}i\" %{Host}i \"%{JSESSIONID}C\" \"%{AWSELB}C\"" combined

Apache HTTPD: logging response header

You just need to add following string to the LogFormat directive from inder httpd.conf:

\"%{HEADER_NAME}o\"

Check MD5 sum of a file on RH

md5sum filename

Monitor outgoing port traffic on Linux

Following command can be used:

netstat -nputw | grep -v "127.0.0.1"

Get Linux and kernel versions

1. Get Linux version:

cat /etc/*release

2. Get kernel version:

uname -r

Fix "Found a swap file by the name"

1. If you get the following:

E325: ATTENTION
Found a swap file by the name ".file.conf.swp"
          owned by: root   dated: Wed Jan  3 11:43:03 2018
         file name: /etc/httpd/conf.d/file.conf
          modified: YES
         user name: root   host name: system-rh
        process ID: 19891
While opening file "file.conf"
             dated: Tue Jan 16 15:51:50 2018
      NEWER than swap file!

(1) Another program may be editing the same file.  If this is the case,
    be careful not to end up with two different instances of the same
    file when making changes.  Quit, or continue with caution.
(2) An edit session for this file crashed.
    If this is the case, use ":recover" or "vim -r file.conf"
    to recover the changes (see ":help recovery").
    If you did this already, delete the swap file ".file.conf.swp"
    to avoid this message.

2. List all hidden files

ls -al

3. Remove troubled swap file:
rm -rf .file.conf.swp