Check Status

cek; status; server; unix; linux; MRO
runlevel
know the current run level


netstat –a    
see the network sessions


netstat –rn  
View the gateways configured


who / finger  
View the Users logged in detail


ps –ef  
view all the running process and its related files


sestatus  
check SELINUX status


service iptables status  
check firewall status


ifconfig –a  
view the network cards and IP address configured


top
provide the top processes, CPU load, memory utilization, swap utilization, running/zombie process, uptime, etc


iostat  
will provide the information about the disk utilization, read/write rate, etc.


dmesg
displays all the server errors including hardware, booting, network errors by retrieve the information from log files which located in /var/log


lsof
used in many Linux/Unix like system that is used to display list of all the open files and the processes. The open files included are disk files, network sockets, pipes, devices and processes.


tcpdump
network packet analyzer or packets sniffer program that is used capture or filter TCP/IP packets that received or transferred on a specific interface over a network.

traceroute 
print the route packets take to network host.


dig $dns_name
tool for interrogating DNS name servers.


nslookup $dns_name
query Internet domain name servers.


w
prints a summary of the current activity on the system, including what each user is doing, and their processes.


nmap $server_name
checks the opened port on the server.


scp $filename user@targethost:/$path
secure copy files to and from another host in the network.


arp
view / add the contents of the kernel’s ARP tables.


iwconfig 
to configure a wireless network interface.


ipnat –l
gives the list of active rules.


ipfstat –l
grants access to a few information on filtered packets, as well as active filtering rules.