varsha Netapp : disk zero spares
cloudibee To clean up the spare disks and zero them, use the below command. Having a zero’d spare disks can reduce time when on volume creation or on volume reconstruction. filer1>…
Linux VLAN configuration
1. Connect the eth0 interface of your linux machine to the switch. 2. Remove the IP Address information on the eth0 interface # ifconfig eth0 0.0.0.0 # ifconfig eth0 up…
Netapp tips : Disk firmware upgrade
After a Netapp failed disk swap, if an autosupport message is sent saying that the disk firmware is downrev, please run the following command. filer1> disk_fw_update Make sure that the…
Xen Wireless
Details on howto setup Xen on WiFi network : http://wiki.xensource.com/xenwiki/XenWifi . Good one.
Xen tutorial
Xen lets you create guest operating systems (*nix operating systems like Linux and FreeBSD), so called “virtual machines” or domUs, under a host operating system (dom0). Using Xen you can…
Files used by process
To check what files are being used by a process, you can use lsof with option -p. Example: # lsof -p 2791COMMAND PID USER FD TYPE DEVICE SIZE NODE NAMEsyslogd…
Xen : Administration commands
Xen Daemons For the Xen server to function properly, the below daemons must be running on the VM server. xend : This is the Xen server control daemon. This daemon…
Managing Xen
Here are some xm and virsh commands for creating, managing, and troubleshooting xen virtual machines. Staring and Stopping VMs xm create – Create a domain based on config file xm…
Dont pipe cat
A basic-but-common grep usage error involves pipe’ing the output of cat to grep to search the contents of a single file. This is absolutely unnecessary and a waste of time,…
Disk information using smartctl
/usr/sbin/smartctl – controls the Self-Monitoring, Analysis and Reporting Technology (SMART) system built into many ATA-3 and later ATA, IDE and SCSI-3 hard drives. The purpose of SMART is to monitor…
How to identify whether the machine supports full-virtual guests?
To run fully virtualized guests, host CPU support is needed. This is typically referred to as Intel VT, or AMD-V. To check for Intel VT support look for the ‘vmx’…
How to identify whether the machine supports para virtual guests?
If the machine supports para virtual guests, then you should see a “pae” flag in /proc/info. This means – the machine has PAE support and can run para virtual guests.…
Netapp – how to identify disk speed
Command: storage show disk –a (or) vol status –r Filer> storage show disk –a Disk: 2b.18Shelf: 1Bay: 2Serial: XYZASDFVendor: NETAPPModel: X266_MTOMC320PADRev: R5VVRPM: 5400WWN: x:200:xxxx:1817d2 Filer> vol status -r RAID Disk…
Netapp performance troubleshooting – nfs_hist
This command displays the latency details of each NFS call and its histogram. Zero the counter with –z option before you start debugging. You should be in advanced privilege to…
Load Average
A very good article on Unix Load averages and how it is calculated . Worth reading for every sysadmin and performance engineers.