Linux Basic Commands and Description – Part 3
ethtool:
# ethtool eth0 (view ethernet device properties)
# ethtool -s eth0 autoneg off (make changes in NIC parameter, use "-s")
# ethtool -s eth0 speed 100 autoneg off duplex full (change the speed of ethernet card)
# ethtool -i eth0 (Display driver settings)
# ethtool -a eth0 (Display Auto-negotiation, RX and TX)
# ethtool -S eth0 (Display Network Statistics)
# ethtool -p eth0 (corresponding LED of physical port to blink)
# ethtool -p eth2 15 (corresponding LED of physical port to blink for 15s)Commands related to NFS:
# showmount (Shows the available shares on your local machine
# showmount -e <server-ip or hostname> (Lists the available shares at the remote server)
# showmount -d (Lists all the sub directories)
# exportfs -v (Displays a list of shares files and options on a server)
# exportfs -a (Exports all shares listed in /etc/exports, or given name)
# exportfs -u (Unexports all shares listed in /etc/exports, or given name)
# exportfs -r (Refresh the server’s list after modifying /etc/exports)
# nfsstat –s (to check nfs server version)
# nfsstat –c (to check nfs client version)Crontab:
“minute” “hour” “date of month” “month” “day of week” “command”
Minute: 0-59
Hour: 0-23
Date of Month: 1-31
Month: 1-12
Day of Week: 0-7, 0 and 7 are Sunday.
# crontab –e (edit cron file)
# crontab –l (list cron jobs)
# crontab –l –u <user> (list cron jobs for user)
Schedule a Job for more than one instance (e.g. Twice a Day)
# 00 11,16 * * * /home/test/test.sh
Schedule a job for specific range of time (Only on weekdays)
# 00 09-18 * * 1-5 /home/test/test.sh
Schedule a Background Cron Job For Every 10 Minutes
# */10 * * * * /home/ramesh/check-disk-spaceCluster Related Commands:
# clustat (To check status of cluster)
# clustat –m (Display status of specific cluster node)
# clustat –s (Display status of specific service)
# clustat –l (Display long format of services)
# cman_tool status (Display local record of cluster status)
# cman_tool nodes (Display local record of cluster nodes)
# ccs_tool lsnode (Display nodes)
# ccs_tool lsfence (List fence devices)
# clusvcadm –e <service_name> (start the service on preferred node)
# clusvcadm –e <servive_name> -m node (start the service on mentioned node)
# clusvcadm –d <service_name> (Stop the service and put it into disable state)
# clusvcadm –r <service_name> -m node (Relocating service on mentioned node)
# clusvcadm –s <service_name> (Stop the service and placed into the stopped state)
# clusvcadm –Z <service_name> (Freeze service on the node where it is currently running)
# clusvcadm –U (Unfreez it)
# clusvcadm –R <servive_name> (Restart a service)Few commands to check shared storage details:
# scsi_id --whitelisted --device=/dev/sdh
# lspci | grep -i HBA
# lspci | grep -i Fibre
# lspci -nn | grep -i hba
# ls -l /dev /dev/mapper |grep '^b'
# ls -l /dev/disk/by-id/
# ls -l /dev/disk/by-path/
# ls -l /dev/disk/by-uuid/
# ls -l /sys/class/fc_host/
# ls -l /sys/block/
# dmesg | grep -i "attached"
# lsblk -o KNAME,TYPE,SIZE,MODEL
# echo "- - -" > /sys/class/scsi_host/host1/scan