Delete SNMPv3 User on Linux

Don’t know if this is the recommended way to delete a user, but it seems to work.

sudo service snmpd stop

Open up the snmpd.conf file in /var/lib and find the line with the SNMP user and delete the line

sudo vi /var/lib/snmp/snmpd.conf

Save, exit, and start snmpd

sudo service snmpd start

These steps work for Ubuntu, but should work for any Debain based distro as well as CentOS, Fedora, RedHat etc.

Add multiple IP bindings to Mikrotik Hotspot – Bash Script

Copy and paste the following into a file named mtbypass.sh and then “chmod +x mtbypass.sh”  Or download from this direct link.  Be sure to change the username and password

#!bin/bash
filelist="bypasslist.txt"
username="admin"
password="password!"
ip="$1"

for i in `cat ${filelist}`
do
address=`echo $i | cut -d= -f1`
mac=`echo $i | cut -d= -f2`
sshpass -p ${password} ssh ${username}@${ip} "ip hotspot ip-binding add address=${address} mac-address=${mac} type=bypassed"
done

Now create a file named bypasslist.txt and put all the addresses you want bypassed.  You’ll need the Mac Address and the IP Address.

Example file

192.168.88.2=4C:5E:0C:B8:4E:01
192.168.88.3=3E:AA:A1:2D:8B:2C
192.168.88.5=DE:D1:39:65:91:4E

Usage of script is

./mtbypass.sh MikrotikIP

Example:

./mtbypass.sh 192.168.88.1

LibreNMS Error: Missing dependencies! Run the following command to fix:

Received this error while trying to access LibreNMS in web browser.

Error: Missing dependencies! Run the following command to fix:

./scripts/composer_wrapper.php install –no-dev

 

Tried sshing into the LibreNMS server and running the script, but that didn’t fix the issue.

Ran ./validate.php and it came up with the some of the following errors.

[FAIL] Missing PHP extension: mbstring
[FIX] Please install mbstring
[FAIL] The poller (localhost.localdomain) has not completed within the last 5 minutes, check the cron job.
[WARN] Your install is over 24 hours out of date, last update: Thu, 7 May 2018 19:18:35 +0000
[FIX] Make sure your daily.sh cron is running and run ./daily.sh by hand to see if there are any errors.

Installed mbstring.  You may need to change the number if yum is complaining about package conflicts.  Use “yum search mbstring” to show all the versions available.

yum install php71w-mbstring

Ran ./validate.php again and it wanted this script run

./scripts/composer_wrapper.php install --no-dev

Restart Apache

systemctl restart httpd

semanage Allow and Delete ports in CentOS

The commands are for CentOS, but should work on Fedora and RedHat.

If semanage is not installed refer to here.

You would typically use this along with the systems firewall to allow a port through.  Guide for firewalld and iptables.  If you change it in the firewall and fail to add/edit it in semanage you can potentially get weird behavior like sshd not wanting to start after changing the port.

Add port

semanage port -a -t ssh_port_t tcp 2222

The above command allows the sshd service to start, using port 2222.

List allowed ports

semanage port -l

You can use grep to filter the results

Example:

[admin@localhost ~]# semanage port -l | grep ssh
ssh_port_t tcp 2222, 22
[admin@localhost ~]#

Delete port

semanage port -d -p tcp 2222

Other examples

Allow SNMP

semanage port -a -t snmp_port_t tcp 2222