Linux filesystem
Linux is a widely used open source operating system. It supports many different types of file systems. Each filesystem has its own advantages and limitations.
VxVM cheatsheet
Veritas Volume Manager (VxVM) enables us to manage physical drives as logical devices. Applications and the operating system see a veritas disk/volume as a physical disc with configurable file systems, databases, and other managed data objects.
For computer and Storage Area Network (SAN) systems, VxVM offers simple online disc storage management. In order to boost I/O throughput and safeguard against hardware failure, VxVM can be configured to support the Redundant Array of Independent Disks (RAID) concept. Moreover, VxVM has capabilities that improve disc failure quick recovery and fault tolerance.
SMTP Reply codes are used to determine the error in the message, SMTP(Simple Mail Transfer Protocol) is a standard protocol for sending emails, the client sends and the server responds, a response is with the 3 digit code which contains the meaning for the response with the codes, find the below SMTP reply codes
sar informations are recorded for each and every second, we can see the current sar data’s as well as historic datas from the sar file, two files are written in the default path of sar configuration. i.e., saXX and sarXX
Use sar -f will get the historic data , example sar -f /var/log/sa/sa10 -r, will show the memory usage for the month day10.