How to Find disk SCSI ID WWIDS In Linux
On Linux disk SCSI ID uniquely identifies each SCSI device on the SCSI bus. A unique SCSI ID is generated when a scsi disk is added to Linux system. SCSI ID can be used for representing a disk in the configuration file because the disk name like sda sdb sdc may change after a server […]
How Disk Multipath works on Linux
Linux Multipath command is used to manage storage SAN (storage area network) disks on OS side. Linux multipath provides a way of organizing the I/O paths logically, by creating a single multipath device on top of the underlying devices. Start multipath on Linux List multipath devices on Linux Get Disk WWID ( SCSI ID ) […]
15 Linux multipath examples third part
Linux Multipath command is used to manage storage SAN (storage area network) disks on OS side. Linux multipath provides a way of organizing the I/O paths logically, by creating a single multipath device on top of the underlying devices. How to get the HBA port name on Linux Show the existing multipath configuration in brief […]
15 Linux multipath examples for Linux admin
Linux Multipath command is used to manage storage SAN (storage area network) disks on OS side. Linux multipath provides a way of organizing the I/O paths logically, by creating a single multipath device on top of the underlying devices. Flush/Remove all the multipath device on Linux # multipath -F Flush/Remove selected multipath device First of […]
15 Linux multipath command examples
Linux Multipath command is used to manage storage SAN (storage area network) disks on OS side. Linux multipath provides a way of organizing the I/O paths logically, by creating a single multipath device on top of the underlying devices. Without DM Multipath, each path from a server node to a storage controller is treated by […]
How to test NFS performance with dd on Linux?
NFS performance is important for the production environment. In this tutorial, we will review how to use DD command to test local storage and NFS storage performance. Test nfs storage performance on Linux There are some differences between each testing command. We choose dd command in the following example. dd – without conv=fsync or oflag=direct. […]
Using Linux nfsiostat to troubleshoot nfs performance issue
Linux command nfsiostat can be used to determine the average Round Trip Time (avg RTT) in milliseconds which is a good measurement for storage performance issue. The nfsiostat command is available in later versions of the nfs-utils package. What does nfsiostat output mean? Understanding nfsiostat command output How to troubleshooting NFS performance? What does nfsiostat […]
What does actimeo mean during NFS mount in Linux? Does this impact storage performance?
actimeo is a common NFS mount option in Linux. actimeo=0 can make a big performance difference in the production environment. What does actimeo mean in nfs mount? The “actimeo=0” option means turn attribute caching off. The actimeo option actually makes the time duration the nfs client holds the various cache attributes like “acregmin”,”acregmax”,”acdirmin” and “acdirmax” […]