Cat
Tail-f
Log file description
/var/log/message system startup information and error logs are one of the most commonly used logs in red Hat Linux/var/log/secure Security-related log information/var/log/maillog message-related log information/var/log /cron log information related to timed tasks/var/log/spooler log messages related to UUCP and news devices/var/log/boot.log Daemon start and stop related log message
System:
# uname-a # View kernel/Os/cpu info # cat/etc/issue # cat/etc/redhat-release # view OS version # Cat/proc/cpuinfo # view CPU Info # Hostname # View Computer name # LSPCI-TV # list all PCI devices # LSUSB-TV # list all USB devices # lsmod # list loaded kernel modules # env # View Environment variables
Resources:
# free-m # View memory usage and swap usage # df-h # View each partition usage # du-sh < directory name > # View the size of the specified directory # grep memtotal/proc/meminfo # Check Look at the total memory # grep Memfree/proc/meminfo # View Idle amount # uptime # View System uptime, number of users, load # cat/proc/loadavg # View System load
Disks and partitions:
# Mount | Column-t # View attached partition status # fdisk-l # View all partitions # swapon-s # view all swap partitions # hdparm-i/DEV/HDA # View disk parameters (IDE devices only) # DME sg | grep IDE # View IDE Device detection status on startup network: # ifconfig # View all network Interface Properties # iptables-l # View firewall settings # route-n # View Routing table # Netstat- LNTP # View all listening ports # NETSTAT-ANTP # View all established connections # netstat-s # View Network statistics
Process:
# ps-ef # View All Processes # top # Real-time display process status
User:
# w # view active user # ID < username > # View specified user information # Last # View user log in log # cut-d:-F1/ETC/PASSWD # View system All users # cut-d:-f1 /etc/group # View system All groups # Crontab-l # View Current user's scheduled tasks
Service:
# chkconfig–list # List all system Services # Chkconfig–list | grep on # Lists all startup system services
Program:
# rpm-qa # View all installed Packages