Sysadmin stuff.
At work all we use is HP servers. It’s either DL or BL series… and anywhere from gen 6 to gen 10. Recently one of our disk shelve StorageWorks D2700 had two HDDs detected as predictive failure. Predictive failure doesn’t make the drive slot amber so it’s difficult for remote …..
Recently I had a Western Digital NAS Red 3TB HDD failed in my server. Server HDDs are connected via MegaRAID SAS 9271-8i HW RAID controller. I have a spare 3TB HDD standing by. But when I tried to set the failed HDD as “removal”… it keeps automatically go into rebuild …..
I recently replaced my home router with a MikroTik router. I further split servers into two groups. 192.168.0.0/24 – Production 192.168.0.1/24 – Dev My Zabbix server sits in production network and some Zabbix clients sits in dev network. For some reason there is some kind of NAT issue preventing Zabbix …..
At one of my my previous work places we utilize multiple Dell SonicWALL network devices. I’ve written an Expect plus a BASH script (yes, two scripts) that can be cron job to auto backup configurations. We needed the Expect script to interact with SonicWall SSH session. By looking at the …..
Munin is a great resource monitoring tool. However, it can easily max out the server resource depending on number of monitored devices. I’ve ran into some disk I/O contention issue on my Munin server. I don’t even have that many monitored devices… only eighteen. There are couple ways to speed …..
For home servers I funnel all emails through a single Postfix SMTP relay via a Gmail account. (On Debian 9 you need to install libsasl2-modules first.) Create /etc/postfix/sasl_passwd file with following content (replace the obvious variables): [smtp.gmail.com]:587 $USER@gmail.com:$PASS Then generate Postfix map file. This will create /etc/postfix/sasl_passwd.db file. …..
This happens when CentOS do a major version release like from 6 to 7. It doesn’t happen immediately but after the new major version has been released for a while they’ll update repository URL from major.minor (e.g. 6.5) version to just a major (6). So it changes from something like …..
Change minimum rebuild speed: By default Linux SW RAID minimum rebuild speed is quite low by today’s storage standard. Regular mechanical HDD easily performs 50MB+ and a SSD easily performs between 250-500MB. The default RAID rebuild minimum speed is 1MB and maximum is 200MB. While the maximum rebuild speed is fine …..
I utilize Dropbox to share completed photos to friends and clients. But the way how my photo editing process works it requires having a folder outside Dropbox. So instead of having two copies of same photos in different locations… I utilize Windows built-in mklink command to create a junction link. …..
It’s very easy to move Let’s Encrypt SSL certificates to new server. If you don’t know who Let’s Encrypt certificate authority is… read up here. All you need to do install Let’s Encrypt on new serer first, then transfer the following directories to same location on new server. /etc/letsencrypt/archive/$SITE /etc/letsencrypt/live/$SITE …..