Sunday, August 14, 2011

Few Basic Monitoring tools

The following monitoring tools can be used to get information about system activities. use these tools to find the performance problem. some of basic monitoring commands -Process Activity Command

When you need to see the running processes on your Linux in real time, you have top as your tool for that. top also displays other info besides the running processes, like free memory both physical and swap and updates the list every five seconds.,

2.vmstat - Report virtual memory statistics

The command vmstat reports information about processes, memory, paging, block IO, traps, and cpu activity.

3.w - Who Is Logged on And What They Are Doing

w displays the information about users currently on machine, and their processes,the current time,how long the system running, how many users are currently logged on, and the system load average for the past 1, 5, and 15 minutes

4.uptime - How Long The System is Running

The uptime command can be used to check how long the server has been running. - process status

The command should be used to display the currently running processes on our systems - Information about free and used memory on the system

The command free displays the total amount of free and used physical and swap memory in the system, as well as the buffers used by the kernel.

7.iostat - Average CPU Load, Disk Activity

The command iostat report CPU statistics and input/output statistics for devices, partitions and network filesystems (NFS).

8.sar - Store Address Register

The sar command is used to collect, report, and save system activity information it reports every 10min system activity

9.mpstat - Multiprocessor Usage

The mpstat command displays activities for each available processor, reports global and per-processor statistics

10.pmap - Process Memory Usage

pmap displays the memory map of a process for the specified pid

11.netstat - network statistics

The command netstat displays network connections, routing tables, interface statistics, masquerade connections, and multicast memberships. - Stack Segment

ss command is used to dump socket statistics. It allows showing information similar to netstat.

13.iptraf - Real-time Network Statistics

The iptraf command is interactive colorful IP LAN monitor. It is an ncurses-based IP LAN monitor that generates various network statistics including TCP info, UDP counts, ICMP and OSPF information, Ethernet load info, node stats, IP checksum errors, and others.

14.tcpdump - Detailed Network Traffic Analysis

The tcpdump is simple command that dump traffic on a network. However, you need good understanding of TCP/IP protocol to utilize this tool. For.e.g to display traffic info about DNS.

15.strace - trace system calls and signals

Trace system calls and signals. This is useful for debugging webserver and other server problems.

16./Proc file system - Various Kernel Statistics

/proc file system provides detailed information about various hardware devices and other Linux kernel information.