
CentOS – How do I safely delete old kernel versions ?
Linuxpackage-cleanup:
Using package-cleanup command which is a part of yum-utils package we can uninstall any number of old kernels automatically. As an example using --oldkernels --count=2 option with package-cleanup command the command…

ZFS – CENTOS Downgrade
ZFSZFS - Downgrade Commands for Centos:
To do the downgrade/re-install dance:
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ZFS – Tuning
ZFSZFS tuning for SAS3 Storage Tank
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ZFS tuning for SAS3 ALL SSD + nVME Storage Tank
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Some more good advice:
SvennD
ZFS-Discuss

ZFS – SNMP
ZFSZFS - SNMP Extend Commands:
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LibreNMS:
https://community.librenms.org/t/zfs-support/1839
https://docs.librenms.org/#Extensions/Applications/#zfs

CentOS – NIC Teaming with LACP
LinuxA Comparison of Features in Bonding and Team
Feature
Bonding
Team
broadcast Tx policy
Yes
Yes
round-robin Tx policy
Yes
Yes
active-backup Tx policy
Yes
Yes
LACP (802.3ad) support
Yes (active only)
Yes
Hash-based…

Debian – How do you select the fastest mirror from the command line?
DebianI want to update my sources.list file with the fastest server from the command line in a fresh Ubuntu Server install. I know this is trivially easy with the GUI, but there doesn't seem to be a simple way to do it from from the command line?
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Automated…

Git – use a proxy
githubConfigure Git to use a proxy
##In Brief
You may need to configure a proxy server if you're having trouble cloning or fetching from a remote repository or getting an error like unable to access '...' Couldn't resolve host '...'.
Consider…

Linux – iproute2 Cheat Sheet
LinuxOverview
iproute2 is the Linux networking toolkit that replaced net-tools (ifconfig, route, arp etc.)
Old style network utilities like ifconfig and route are still there just for backwards compatibility
and do not provide access to…

Linux – Permissions
Linux
In order to update and change file permissions, you can use the chmod command. The format of the command is as follows:
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for each action
Changing Permissions
VALUE
MEANING
rwx+ugo
No…

Debian – How to disable snmpd ia_addr insert messages?
DebianYou have Debian and Ubuntu servers which runs snmpd service and are getting following message every 30 seconds within /var/log/syslog
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This problem is related with the log level start options of snmpd service
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With…