How To Enable/Disable SELinux

Posted on December 24, 2014 by admin

Disable SELinux

You can manually edit the SELinux config file in /etc/selinux/config and change the variable SELINUX=enforcing to disabled

vi /etc/selinux/config

...
SELINUX=disabled
...

or you can use this little command

sed -i.bak -e 's/^SELINUX=.*/SELINUX=disabled/g' /etc/selinux/config

Enable SELinux

You can enable SELinux manually the same as above but set SELINUX=disabled to SELINUX=enforcing

vi /etc/selinux/config

...
SELINUX=enforcing
...

sed -i.bak -e 's/^SELINUX=.*/SELINUX=enforcing/g' /etc/selinux/config

How to Allow a Port Through Firewalld

Posted on December 24, 2014 by admin

Note: If you have SELinux enabled you’ll need to allow the port in semanage.

Basic syntax

 firewall-cmd --zone=public --add-port=(port number)/(protocal)

So the command to allow port 80 through the firewall would be

firewall-cmd --zone=public --add-port=http/tcp
or
firewall-cmd --zone=public --add-port=80/tcp

The above command only works for the running instance of firewalld. If you want to add the port permanetely you need to run the above command and then run it again with “–permanent” added to the end of the command.

example:

firewall-cmd --zone=public --add-port=http/tcp
firewall-cmd --zone=public --add-port=http/tcp --permanent

How To Install Zenoss 4.2.5 on CentOS 6.5

Posted on December 18, 2014 by admin

First you need to remove mysql-libs

yum remove mysql-libs

Install wget

yum install -y wget

Download the Zenoss install script archive

wget https://github.com/zenoss/core-autodeploy/tarball/4.2.5 -O auto.tar.gz

Extract the archive

tar zxvf auto.tar.gz

and execute the install script

cd zenoss-core-autodeploy-*
./core-autodeploy.sh

Follow the prompts and when it’s finished navigate to http://yourserverip:8080 to complete the install.

Install Wireless Broadcom Driver for Fedora 21

Posted on December 16, 2014 by admin

Run the following commands as root

rpm -Uvh http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-stable.noarch.rpm
rpm -Uvh http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-stable.noarch.rpm

Update the system and then download the driver.

yum update
yum install kmod-wl

When the above commands finish reboot the computer

reboot

How To “Unblock” an IP from cPHulk from the Command Line

Posted on December 10, 2014 by admin

cPHulk uses a MySQL database to keep track of different IP’s to block, white list, black list, etc.

When there have been X amount of failed login attempts from an IP, cPHulk adds an entry for the IP in the brutes table.

To “unblock” the IP we need to delete the entry.

open up the cPHulk MySQL database.

root@localhost [~]# mysql cphulkd

If your interested you can view all tables that cPHulk uses.

show tables;

Take a look at all the IP’s in the brutes table.

SELECT IP FROM brutes;

example:

mysql> SELECT IP FROM brutes;
+---------------+
| IP            |
+---------------+
| 30.134.41.221 |     <--  IP we want to unblock
| 31.134.40.251 |
+---------------+
2 rows in set (0.00 sec)

mysql>

To unblock the IP we just need to delete the row that has the IP address we want.

mysql> DELETE FROM brutes WHERE IP="30.134.41.221";

It should return the following.

mysql> DELETE FROM brutes WHERE IP="30.134.41.221";
Query OK, 1 row affected (0.00 sec)

mysql>

Exit MySQL.

mysql> exit
Bye
root@localhost [~]#

How To Install Ubiquiti mFi controller on Debain(7.5.0) Linux

Posted on December 8, 2014 by admin

Add the following line to /etc/apt/sources.list

deb http://dl.ubnt.com/mfi/distros/deb/debian debian ubiquiti

Add GPG keys

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv C0A52C50

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv 7F0CEB10

Update the system

sudo apt-get update

Install the mFi software

sudo apt-get install mfi

Once it is finished installing you should be able to browse to https://yourserverip:6443 to access the mFi web page.

How To Install Ubiquiti’s UniFi Controller on Debian Linux

Posted on December 8, 2014 by admin

First add the following line to /etc/apt/sources.list

deb http://www.ubnt.com/downloads/unifi/distros/deb/debian debian ubiquiti

Next add the GPG key for UniFi and mongo-10

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv C0A52C50

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv 7F0CEB10

Update the system

sudo apt-get update

Install the UniFi software

sudo apt-get install unifi-rapid

Once it is finished installing you should be able to browse to https://yourserverip:8443 to access the UniFi web page.

How to View Installed Programs in linux

Posted on September 30, 2014 by admin

Debian Based Distros

The below command should work for Debain, Ubuntu, and the Raspberry Pi Raspbian.

dpkg --get-selections

RPM Based Distros

The following works on Fedora, CentOS, ReHat.

rpm -qa

The above commands return all of the packages installed on a system. If you want to look for a specific program or package you can use grep to filter the results.

rpm -qa | grep program

dpkg --get-selections | grep program

SNMP and Shell Script

Posted on September 10, 2014 by admin

First you will need to make sure SNMP is installed.

apt-get install snmpd snmp snmp-mibs-downloader

You’ll need to configure a new snmpd.conf file with

snmpconf

Run through the steps and when your done replace your current snmpd.conf file in /etc/snmp/ with the new one.

Now open up your new snmpd.conf file

vi /etc/snmp/snmpd.conf

and add the following to the bottom of the file.

extend myshscript /path/to/your.sh

Save and close the file and restart the snmpd service.

service snmpd restart

Now we need to find the OID of our new data point. Do this by running

snmpwalk -v2c -c public localhost .1.3.6.1.4.1.8072.1.3.2

It should display something similar to the following.

root@localhost:/etc/snmp# snmpwalk -v2c -c public localhost .1.3.6.1.4.1.8072.1.3.2
iso.3.6.1.4.1.8072.1.3.2.1.0 = INTEGER: 1
iso.3.6.1.4.1.8072.1.3.2.2.1.2.4.118.111.108.116 = STRING: "/etc/snmp/volt.sh"
iso.3.6.1.4.1.8072.1.3.2.3.1.4.4.118.111.108.116 = INTEGER: 0
iso.3.6.1.4.1.8072.1.3.2.4.1.2.4.118.111.108.116.1 = STRING: "14.3"
root@localhost:/etc/snmp#

The OID we are interested in is the one on the last line. If you run a snmpwalk command with the OID you should get your data point.

root@localhost:/etc/snmp# snmpwalk -v2c -c public localhost 1.3.6.1.4.1.8072.1.3.2.4.1.2.4.118.111.108.116.1
iso.3.6.1.4.1.8072.1.3.2.4.1.2.4.118.111.108.116.1 = STRING: "14.3"
root@localhost:/etc/snmp#

All that’s left is to add the OID to your SNMP monitor. If You run into issues with your SNMP server not monitoring the OID, you might need do what I did in the above command, replace the beginning of the OID “iso.” with a “1”.

How to Create a LVM Logical Volume in Linux

Posted on June 19, 2014 by admin

First we need to create the Physical Volume. Change “/dev/sda2” to your drive.

pvcreate /dev/sda2

Next we create the Volume Group. You can change “VGname” to something else if you so desire.

vgcreate VGname /dev/sda2

And finally, create the Logical Volume. The Logical Volume’s name will be home. Change as needed.

lvcreate -l %100FREE -n home VGname

The above command will create a Logical Volume that uses all the free space avaliable in the Volume Group. If you want the Logical Volume to be a specific size, change “-l 100%FREE” to “-L 60G”. Where “60G” is the size in GB.
Example:

lvcreate -L 60G -n home VGname

Your Logical Volume should be setup now. You can list all your Logical Volumes with

lvdisplay

You may need to format the new logical volume to mount it. Replace VGname and LVname for the Volume Group name and the Logical Volume name.

mkfs.ext4 /dev/VGname/LVname

Mount it with

mount /dev/VGname/LVname /mount/point

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Tag Archives: linux