December 2, 2018 in Internet of Things

Implement SAR on Server

(SAR)System Activity Report is used to real-time monitor the various Linux systems like centos, RHEL, Ubuntu, etc. It gives real-time monitoring report of CPU, Memory utilization & Disk IO operations. It collects all real-time performance data, stores them and allows us to historical analysis & identify the bottlenecks Here we will look how to install, configure the utility & perform few commands to understand  server performance statistics
Following performance statistics can be derived using SAR command

1. CPU usage
2. Individual CPU usage
3. Memory, Swap available & used
4. I/O activities of the system
5. Disk I/O activities
6. Network usage & statics
7. Load average data
8. Generate sar report on data from specific time

So, let’s begin

Installation

1. Installation on RHEL/Centos/Amazon Linux
   

   yum install sysstat –y  chkconfig sysstat on  service sysstat start

2. Installation on Ubuntu
   

   apt-get install sysstat update-rc.d sysstat defaults service sysstat start

3. Check installation status
   1. RHEL/Centos/Amazon Linux
      

      rpm -qa sysstat

      

   2. Ubuntu
      

      dpkg-query –show sysstat

      

Configuration of SAR utility

Here, we can specify the duration of log files i.e. how long my log files will be stored on server. Also we could specify the compressing technique, compressing duration etc.

1. Configuration file in RHEL/Centos/Amazon Linux
   

   cat /etc/sysconfig/sysstat

   

2. Configuration in Ubuntu
   

   cat  /etc/default/sysstat

   

3. Crontab file on RHEL/Centos/Amazon Linux/Ubuntu
   

   cat /etc/cron.d/sysstat

   

4. We can see the log file in below location
   

   cd /var/log/sa/

Hands-On

1. CPU utilization
   

   sar -u

   

2. Memory utilization
   

   sar -r

   

3. Generate specific days wise CPU utilization report
   

   cd /var/log/sa && sar -u -f sa19

   

4. Generate specific day wise Memory utilization report
   

   cd /var/log/sa && sar -r -f sa19

   

5. Generate Network statistics report
   

   sar –n ALL

   

6. Generate Block device report
   

   sar -d

   

7. Real time Memory monitoring. Below command will generate memory utilization report by interval of 2 seconds with 5 records.
   

   sar -r 2 5

   

8. Generate Load average report
   

   sar -q

   

9. Generate and save report into a file
   

   sar -r >> sar-mem.txt

   

10. Generate disk I/O and transfer rate statistics
    

    sar -b

    

11. Generate swap statistics
    

    sar -S

    

 
 
 

Contributed by : Sonali Shah

https://www.linkedin.com/in/sonali-shah/