[20260815]centos 9 sar安装.txt

--//发现安装的centos 9，没有sar命令
# sar
bash: sar: command not found...
Failed to search for file: /mnt/cdrom/BaseOS was not found

# mount /dev/sr0 /mnt/cdrom/ -o ro
# sar
bash: sar: command not found...
Install package 'sysstat' to provide command 'sar'? [N/y] n

--//需要安装sysstat包。

# dnf install --setopt=tsflags=test -y sysstat
29cbaseos                                                                                                                                                                                                                                       2.2 MB/s | 2.3 kB     00:00
29cappstream                                                                                                                                                                                                                                    2.7 MB/s | 2.8 kB     00:00
Dependencies resolved.
===================================================================================
 Package                  Architecture    Version         Repository          Size
===================================================================================
Installing:
 sysstat                  x86_64          12.5.4-11.el9   henry_appstream    480 k
Installing dependencies:
 lm_sensors-libs          x86_64          3.6.0-10.el9    henry_appstream     42 k

Transaction Summary
===================================================================================
Install  2 Packages

Total size: 522 k
Installed size: 1.6 M
DNF will only download packages, install gpg keys, and check the transaction.
Downloading Packages:
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Complete!

--//执行安装任务：
#  dnf install -y sysstat
Last metadata expiration check: 0:04:20 ago on Sun 16 Aug 2026 11:35:00 AM CST.
Dependencies resolved.
===============================================================================
 Package                  Architecture  Version        Repository         Size
===============================================================================
Installing:
 sysstat                  x86_64        12.5.4-11.el9  henry_appstream   480 k
Installing dependencies:
 lm_sensors-libs          x86_64        3.6.0-10.el9   henry_appstream    42 k

Transaction Summary
===============================================================================
Install  2 Packages

Total size: 522 k
Installed size: 1.6 M
Downloading Packages:
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Preparing        :                                                                                                               1/1
  Installing       : lm_sensors-libs-3.6.0-10.el9.x86_64                                                                           1/2
  Installing       : sysstat-12.5.4-11.el9.x86_64                                                                                  2/2
  Running scriptlet: sysstat-12.5.4-11.el9.x86_64                                                                                  2/2
Created symlink /etc/systemd/system/multi-user.target.wants/sysstat.service → /usr/lib/systemd/system/sysstat.service.
Created symlink /etc/systemd/system/sysstat.service.wants/sysstat-collect.timer → /usr/lib/systemd/system/sysstat-collect.timer.
Created symlink /etc/systemd/system/sysstat.service.wants/sysstat-summary.timer → /usr/lib/systemd/system/sysstat-summary.timer.

  Verifying        : lm_sensors-libs-3.6.0-10.el9.x86_64                                                                           1/2
  Verifying        : sysstat-12.5.4-11.el9.x86_64                                                                                  2/2

Installed:
  lm_sensors-libs-3.6.0-10.el9.x86_64     sysstat-12.5.4-11.el9.x86_64
Complete!

# systemctl status sysstat
○ sysstat.service - Resets System Activity Logs
     Loaded: loaded (/usr/lib/systemd/system/sysstat.service; enabled; preset: enabled)
     Active: inactive (dead)

# systemctl enable --now sysstat

--//简单测试：
# sar -u 1 5
Linux 5.14.0-704.el9.x86_64 (centos9)   08/16/2026      _x86_64_        (4 CPU)

11:45:15 AM     CPU     %user     %nice   %system   %iowait    %steal     %idle
11:45:16 AM     all      0.00      0.00      0.00      0.00      0.00    100.00
11:45:18 AM     all      0.00      0.00      0.48      0.00      0.00     99.52
11:45:19 AM     all      0.00      0.00      0.25      0.00      0.00     99.75
11:45:20 AM     all      0.00      0.00      0.00      0.00      0.00    100.00
11:45:21 AM     all      0.00      0.00      0.25      0.00      0.00     99.75
Average:        all      0.00      0.00      0.20      0.00      0.00     99.80

--//检查配置:
# grep -v "^#" /etc/sysconfig/sysstat | sed -e "/^$/d"
HISTORY=28
COMPRESSAFTER=31
SADC_OPTIONS=" -S DISK"
SA_DIR=/var/log/sa
ZIP="xz"
DELAY_RANGE=0
UMASK=0022