![\"Image](\"\/blog\/wp-ttn-blog\/uploads\/2024\/01\/5654683066_6703251656.jpg\")
<\/p>\nMonitoring servers are very important for\u00a0every\u00a0server administrator. There are some command line tools available to monitor server resource usages like top, vmstat, etc.<\/p>\n
<\/p>\n
SAR or sar provides almost all the resource usages reports which we get from many different tools at one place but more importantly\u00a0is could keep a\u00a0record of the data which can be used\u00a0for\u00a0historical analysis to identify bottlenecks. With the tool, you can check the performance\u00a0report of a specific time.<\/span><\/strong><\/p>\n Installation is pretty simple, you just need to install sysstat\u00a0<\/strong>tool using apt as below:<\/p>\n After we have installed sar we will need to configure\u00a0it to collect and store performance data on a regular\u00a0interval.<\/p>\n To do that we will enable sadc\u00a0by modifying\u00a0configuration\u00a0file “\/etc\/default\/sysstat<\/strong>”<\/p>\n [js]# Should sadc collect system activity informations? Valid values After this, a cronjob will start collecting the SAR\u00a0report every 10 min, but we would want that report to be collected much sooner so we will change the cronjob to run every min:<\/p>\n That is All! We now have a working SAR tool which records all performance\u00a0related data.<\/p>\n You can now use the\u00a0sar<\/strong> command to get the performance report as below:<\/p>\n Some important command line option which we can use: You can set repetition and interval with any command for desired output:<\/p>\n You can now check the reports that have been collected in the past by specifying time and day:Installation<\/h2>\n
sudo apt-get install sysstat<\/pre>\n
Configuration<\/h2>\n
sudo vi \/etc\/default\/sysstat<\/pre>\n
\n# are "true" and "false". Please do not put other values, they
\n# will be overwritten by debconf!
\nENABLED="true"[\/js]<\/p>\nsudo vi \/etc\/cron.d\/sysstat\r\n<\/pre>\n
# Activity reports every 10 minutes everyday \r\n* * * * * root command -v debian-sa1 > \/dev\/null && debian-sa1 1 1<\/pre>\n
Usage<\/h2>\n
![\"Sar](\"\/blog\/wp-ttn-blog\/uploads\/2016\/09\/Selection_014.png\")
<\/p>\n
\n-u<\/strong> CPU Usage of ALL CPUs
\n-q<\/strong> Reports run queue and load average
\n-r<\/strong> Memory Free and Used
\n-S<\/strong> Swap Space Used
\n-b<\/strong> Overall I\/O Activities
\n-d<\/strong> Individual Block Device I\/O Activities
\n-n<\/strong> Report network statistics<\/p>\nsar[ interval [ count ]]<\/pre>\n
\n-s hh:mm[:ss] start time
\n-e hh:mm[:ss] end time
\n-f \/var\/log\/sysstat\/sa[DD] on a specific day,
\nNote:<\/strong>\u00a0If you have just installed and configured the sar you might not get the directory, full day report get written to the folder in midnight.<\/p>\n