pstreeコマンドがなかったのでインストールしてみました

# pstreeを入力
[root@ik1-305-12909 subNewDir3]# pstree
コマンドがないのでインストールする
-bash: pstree: command not found
[root@ik1-305-12909 subNewDir3]# yum install psmisc
実行結果は以下になります
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * base: ftp.iij.ad.jp
 * epel: mirror.dmmlabs.jp
 * extras: ftp.iij.ad.jp
 * updates: ftp.iij.ad.jp
Resolving Dependencies
--> Running transaction check
---> Package psmisc.x86_64 0:22.20-15.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

========================================================================================================================================================================
 Package                                Arch                                   Version                                       Repository                            Size
========================================================================================================================================================================
Installing:
 psmisc                                 x86_64                                 22.20-15.el7                                  base                                 141 k

Transaction Summary
========================================================================================================================================================================
Install  1 Package

Total download size: 141 k
Installed size: 475 k
Is this ok [y/d/N]: y
Downloading packages:
psmisc-22.20-15.el7.x86_64.rpm                                                                                                                   | 141 kB  00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : psmisc-22.20-15.el7.x86_64                                                                                                                           1/1
  Verifying  : psmisc-22.20-15.el7.x86_64                                                                                                                           1/1

Installed:
  psmisc.x86_64 0:22.20-15.el7

Complete!
# pstreeを再入力
[root@ik1-305-12909 subNewDir3]# pstree
実行結果は以下になります
systemd-+-NetworkManager---2*[{NetworkManager}]
        |-abrt-watch-log
        |-abrtd
        |-2*[agetty]
        |-atd
        |-auditd---{auditd}
        |-chronyd
        |-crond
        |-dbus-daemon
        |-fail2ban-server---2*[{fail2ban-server}]
        |-firewalld---{firewalld}
        |-lsmd
        |-lvmetad
        |-master-+-pickup
        |        `-qmgr
        |-polkitd---5*[{polkitd}]
        |-rsyslogd---2*[{rsyslogd}]
        |-smartd
        |-sshd---sshd---bash---pstree
        |-systemd-journal
        |-systemd-logind
        |-systemd-udevd
        |-tuned---4*[{tuned}]
        `-wpa_supplicant
        ```
参照元はこちらです。（ありがとうございます）
https://qiita.com/todanano/items/f421c237eaa2d9adff04