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| language | bash |
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| theme | Midnight |
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vmstat -s
980492 K total memory
480208 K used memory
132040 K active memory
582364 K inactive memory
67924 K free memory
21724 K buffer memory
410636 K swap cache
0 K total swap
0 K used swap
0 K free swap |
free -h # Displays memory usage in "human-readable" format
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du -sh /path/to/directory Displays # Displays the size of a specific directory.
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Managing processes and services is essential for maintaining system stability.
- ps
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- aux # Lists all running processes
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ps aux
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.0 168800 10944 ? Ss Jun12 0:02 /sbin/init
root 2 0.0 0.0 0 0 ? S Jun12 0:00 [kthreadd]
root 3 0.0 0.0 0 0 ? I< Jun12 0:00 [rcu_gp]
root 4 0.0 0.0 0 0 ? I< Jun12 0:00 [rcu_par_gp]
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systemctl status service_name name # Checks the status of a service
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systemctl status apache2
● apache2.service - The Apache HTTP Server
Loaded: loaded (/lib/systemd/system/apache2.service; enabled; vendor preset: enabled)
Active: active (running) since Wed 2024-05-29 16:06:04 UTC; 2 weeks 5 days ago
Docs: https://httpd.apache.org/docs/2.4/
Process: 1000205 ExecReload=/usr/sbin/apachectl graceful (code=exited, status=0/SUCCESS)
Main PID: 40385 (apache2)
Tasks: 55 (limit: 1013)
Memory: 8.8M
CPU: 1min 55.654s
CGroup: /system.slice/apache2.service
├─ 40385 /usr/sbin/apache2 -k start
├─1000209 /usr/sbin/apache2 -k start
└─1000210 /usr/sbin/apache2 -k start |
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| language | bash |
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| theme | Midnight |
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kill - |
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| language | bash |
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| theme | Midnight |
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kill -9 process_id(PID) # Forces termination of a process.
(No output unless there is an error, the process is terminated forcefully) |
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dmesg -T
[Wed May 29 14:46:00 2024] Run /init as init process
[Wed May 29 14:46:00 2024] with arguments:
[Wed May 29 14:46:00 2024] /init
[Wed May 29 14:46:00 2024] with environment:
[Wed May 29 14:46:00 2024] HOME=/
[Wed May 29 14:46:00 2024] TERM=linux
[Wed May 29 14:46:00 2024] BOOT_IMAGE=/boot/vmlinuz-5.15.0-97-generic
[Wed May 29 14:46:00 2024] biosdevname=0
[Wed May 29 14:46:00 2024] netcfg/do_not_use_netplan=true
[Wed May 29 14:46:00 2024] piix4_smbus 0000:00:01.3: SMBus Host Controller at 0x700, revision 0
[Wed May 29 14:46:00 2024] scsi host2: Virtio SCSI HBA
[Wed May 29 14:46:00 2024] scsi 2:0:0:0: Direct-Access QEMU QEMU HARDDISK 2.5+ PQ: 0 ANSI: 5
[Wed May 29 14:46:00 2024] input: VirtualPS/2 VMware VMMouse as /devices/platform/i8042/serio1/input/input4
[Wed May 29 14:46:00 2024] input: VirtualPS/2 VMware VMMouse as /devices/platform/i8042/serio1/input/input3
[Wed May 29 14:46:00 2024] cryptd: max_cpu_qlen set to 1000 |
journalctl # Views systemd logs and allows filtering Linux system logs to extract relevant information for monitoring and troubleshooting. How To Use journalctl
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journalctl
-- Logs begin at Tue 2024-06-18 10:55:23 UTC, end at Tue 2024-06-18 12:06:19 UTC. --
Jun 18 10:55:23 hostname kernel: Linux version 5.4.0-74-generic (buildd@lcy01-amd64-013) (gcc version 9.3.0 (Ubuntu 9.3.0-17ubuntu1~20.04)) #83-Ubuntu SMP Thu May 6 10:34:06 UTC 2021 (Ubuntu 5.4.0-74.83-generic 5.4.101)
Jun 18 10:55:23 hostname kernel: Command line: BOOT_IMAGE=/boot/vmlinuz-5.4.0-74-generic root=UUID=5d7f5dcd-1234-5678-9abc-def012345678 ro quiet splash vt.handoff=7
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journalctl -u service_name # Views Logs for a Specific Service
journalctl # Views systemd logs and allows filtering Linux system logs to extract relevant information for monitoring and troubleshooting. How To Use journalctl
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journalctl
-- Logs begin at Tue 2024-06-18 10:55:23 UTC, end at Tue 2024-06-18 12:06:19 UTC. --
Jun 18 10:55:23 hostname kernel: Linux version 5.4.0-74-generic (buildd@lcy01-amd64-013) (gcc version 9.3.0 (Ubuntu 9.3.0-17ubuntu1~20.04)) #83-Ubuntu SMP Thu May 6 10:34:06 UTC 2021 (Ubuntu 5.4.0-74.83-generic 5.4.101)
Jun 18 10:55:23 hostname kernel: Command line: BOOT_IMAGE=/boot/vmlinuz-5.4.0-74-generic root=UUID=5d7f5dcd-1234-5678-9abc-def012345678 ro quiet splash vt.handoff=7
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journalctl -u service_name # Views Logs for a Specific Service
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journalctl -u apache2
-- Logs begin at Tue 2024-06-18 10:55:23 UTC, end at Tue 2024-06-18 12:05:19 UTC. --
Jun 18 11:56:19 hostname systemd[1]: Starting The Apache HTTP Server... |
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journalctl -u apache2
-- Logs begin at Tue 2024-06-18 10:55:23 UTC, end at Tue 2024-06-18 12:05:19 UTC. --
Jun 18 11:56:19 hostname systemd[1]: Starting The Apache HTTP Server...
Jun 18 11:56:19 hostname apache2[1342]: AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message
Jun 18 11:56:19 hostname systemd[1]: Started The Apache HTTP Server. |
tail /var/log/syslog # Shows the last part of the logs, where problems usually lie.
apache2[1342]: AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message
Jun 18 11:56:19 hostname systemd[1]: Started The Apache HTTP Server. |
tail /var/log/syslog # Shows the last part of the logs, where problems usually lie.
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tail /var/log/syslog
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tail /var/log/syslog
Jun 18 16:25:01 user CRON[777810]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
Jun 18 16:27:02 user dbus-daemon[756]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.49' (uid=1000 pid=1527 comm="/usr/lib/x86_64-linux-gnu/libexec/org_kde_powerdev" label="unconfined") (using servicehelper)
Jun 18 16:2725:0201 user dbus-daemonCRON[756777810]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper' (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
Jun 18 16:2927:0802 user dbus-daemon[756]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.49' (uid=1000 pid=1527 comm="/usr/lib/x86_64-linux-gnu/libexec/org_kde_powerdev" label="unconfined") (using servicehelper)
Jun 18 16:2927:0802 user dbus-daemon[756]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
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| CSS Stylesheet |
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.home-banner {
background: #459df0;
color: #fff;
font-size: 20px;
padding: 20px;
}
.home-banner h2 {
color: #fff;
}
.title-box {
border: 1px none #459df0;
padding: 10px;
}
.title-box > h2 {
background: #459df0;
bottom: 10px;
color: #fff;
margin-left: -10px;
margin-right: -10px;
padding: 2px 10px;
position: relative;
} |
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