As the amount of data we store continues to grow and grow, there is bound to become a time that you will need to resize your partitions to add more disk space. On our of my MySQL replication virtual servers, I created it initially with a 200GB disk. After moving all the data over, was wishing I would have had a bit more space. Good news is this can easily be done. I should note that I am using raw image files, not lvms, so there is a bit more work required.
I recently replaced one of our cPanel DNS-only nameservers. Typically we run our DNS servers with 512MB of memory, because why would a simple DNS server need any more than that? I was shocked to see that cPanel, even the free DNS-only version, now requires 768MB of memory if you’re using CentOS7/RHEL6 or 1GB if you’re using CentOS7/RHEL7. If you are like us and are using a VPS to host your DNS, this can double your cost spent to maintain your DNS servers.
ClamAV is an open source anti-virus utility for Linux designed to detect viruses, malware, and our favorite – php script exploits. It does a great job at picking up php files containing backdoors, remote file managers, spam mailer bots, etc. We run this on all of our hosting servers daily. It is especially useful for detecting and removing files uploaded by the numerous exploitable Wordpress 3rd party plugins.
There are many reasons why a server admin may want to run multiple instances of MySQL on the same physical server. These could include consolidating physical servers, increasing uptime per product, or to fully utilize existing hardware. In our case, we want to set up a separate MySQL instance to house Zabbix database. Zabbix is an open source systems monitoring platform. We want this database to remain online as much as possible, even when we are performing maintenance to our main MySQL database. Spinning up a separate MySQL instance isn’t difficult at all.