Crontab time format
|——————————- Minute (0-59) | |————————- Hour (0-23) | | |——————- Day of the month (1-31) | | | |————- Month (1-12; or JAN to DEC) | … Continue reading →
SEEI
Set default kernel version to use at boot time
Applies to: Fedora 38 and higher, Centos 7 and higher See which kernel version you will boot into on next boot: root@mysystem:~# grubby –default-kernel /boot/vmlinuz-6.9.4-100.fc39.x86_64 Review all kernels you have on your system root@mysystem:~# grubby –info=ALL index=0 kernel=”/boot/vmlinuz-6.9.4-200.fc40.x86_64″ args=”ro rhgb … Continue reading →
I need to find this computer
This is an outline on how to find where a piece of equipment is connected to a network using Juniper switches and a Juniper SRX. The concepts are the same when using other manufacturer’s equipment, but the commands will change. … Continue reading →
Quick And Dirty Mass Emailer Using Swaks
Tested on Fedora 39 Install swaks sudo dnf -y install swaks Create a text file with the email address of every recipient – one email address per line. Name the file list.txt Create a html file that is your email. … Continue reading →
RemoteDesktop on Linux
The following has been tested on Fedora 39, 40 and 41 and Rocky 9 First – install the software sudo dnf -y install xrdp xorgxrdp-glamor edit /etc/xrdp/xrdp.ini Find the line [Xvnc]. Comment out that section by putting a # in … Continue reading →
Use virt-manager as a non-root user on Linux
First check if group already exist, if not create it sudo getent group | grep libvirt If it doesn’t exist, add it as a system group. sudo groupadd –system libvirt Add your user account to the group and log onto … Continue reading →
Moving a KVM virtual guest using cli
The following is the way to perform cold KVM migration. A cold migration involves shutting down the guest server during the migration. Generally speaking, to move KVM VM, you need to copy all the VM data from the source host … Continue reading →
tftp and firewall-cmd
Update – I installed fedora 41 and my original fix below did not work any more New fix firewall-cmd –permanent –new-policy tftp-client-data firewall-cmd –permanent –policy tftp-client-data –add-ingress-zone HOST firewall-cmd –permanent –policy tftp-client-data –add-egress-zone ANY firewall-cmd –permanent –policy tftp-client-data –add-service tftp … Continue reading →
Update Nagios Web Page Title
I have several Nagios web sites I monitor. Problem is you open multiple tabs in firefox and all you see is the Nagios icon and the word “Nagios” so I cant tell which tab is for which server. So I … Continue reading →
Using nagios to monitor port status on ethernet switches
First, we need to identify the id of the ports we want to monitor. On the console of the machine you are running nagios, execute the following commands snmpwalk -v 1 -c MySNMPCommunity my.switch.ip.address ifDescr you will get something like … Continue reading →