blog.kevinfowler.net

To use journalctl to view the logs of the last reboot use the following:

journalctl --boot=-1

This command is handy for viewing logs right before a crash. Do the above command then use shift-g to go to the bottom of the list.

To find the install history of a specific RPM do the following:

rpm -q  --last

To find the install history of all RPMs do the following:

rpm -qa --last

NOTE: This will not sort them by install date.

Run the following command to connect

openssl s_client -connect {server}:{port} -starttls smtp

Then find out what authentication is supported. It should now show "AUTH LOGIN" now that you have an encrypted connection:

ehlo {domain.com}

If you see "AUTH LOGIN" in the list then do the following:

List all zones:

 firewall-cmd --list-all-zones

List all active zones:

firewall-cmd --get-active-zone

To add a host or network to allow all connections from:

firewall-cmd --permanent --zone=trusted --add-source=10.10.10.10

Add a service to be allowed from anywhere:

firewall-cmd --permanent --add-service=smtp

When you run firewall-cmd with the "--permanent" it will not be active until the dameon is reloaded. Do the following to make them active:

firewall-cmd --reload

Here is a quick way to get the current epoch with the date command:

date +%s

If you find your Fn keys don't work like volume up/down try the following:

su -
echo asus-nb-wmi > /etc/modules-load.d/asus-nb-wmi.conf
reboot

In Fedora, the badblocks program is part of the e2fsprogs program. You probably already have that installed. But in case you don't do the following:

yum install e2fsprogs

To just see the bad blocks the following to do a non-destructive read/write test:

badblocks -nvs /dev/sda

To generate generate a list of the bad blocks do the following:

badblocks -nv /dev/sda > badblocks.txt

Now you can mark the bad blocks found with the following:

NOTE: This is an update from my previous post on sharing the desktop or running a VNC Server. This method works great in Fedora 18.

First install the vino package:

yum install vino

Then click on Activities in the top left corner of the screen.

Next type in "vino" and click on "Desktop Sharing" under Applications or under Settings.

Next click "Allow other users to view your desktop". Make sure "Allow other users to control my desktop" is also check.

First download dispcalGUI. It's a GUI to the command line program Argyll. It can be downloaded here: http://dispcalgui.hoech.net/#download For Fedora get the correct RPM version. Then install with yum (replace filename with your version):