lk/system/systemd/journal.md

---
title: "journal"
tags: [ "Documentation", "systemd" ]
---

See a running log of all system messages:


```bash
journalctl -f
```

Or just one unit (`sshd`):

```bash
journalctl -f -u sshd
```

Find errors since November

```bash
journalctl --since=2018-11-01 --grep="EXT4-fs error"
```

Limit size to 2G.

```bash
journalctl --vacuum-size=2G
```

Log the fact that you've installed your own `dnsmasq` on your system to `journalctl`, so that you can notice why your system's broken:


```bash
logger "Installed new dnsmasq"
sudo journalctl -f
```
add headers to lk 2022-01-16 18:20:39 +00:00			`---`
			`title: "journal"`
more cleanup 2022-01-26 22:35:07 +00:00			`tags: [ "Documentation", "systemd" ]`
add headers to lk 2022-01-16 18:20:39 +00:00			`---`
more journalctl checks 2024-02-28 17:45:21 +00:00
			`See a running log of all system messages:`


			```bash
			`journalctl -f`
			```

			Or just one unit (`sshd`):

			```bash
			`journalctl -f -u sshd`
			```

initial commit 2020-01-02 00:04:35 +00:00			`Find errors since November`

change formatting input examples are now given as ```bash input $ARG1 ``` While outputs use md's '> ' sign as a quote. 2023-06-17 19:28:20 +00:00			```bash
			`journalctl --since=2018-11-01 --grep="EXT4-fs error"`
			```
initial commit 2020-01-02 00:04:35 +00:00
			`Limit size to 2G.`

change formatting input examples are now given as ```bash input $ARG1 ``` While outputs use md's '> ' sign as a quote. 2023-06-17 19:28:20 +00:00			```bash
			`journalctl --vacuum-size=2G`
fix journal command 2024-02-28 17:36:56 +00:00			```

more journalctl checks 2024-02-28 17:45:21 +00:00			Log the fact that you've installed your own `dnsmasq` on your system to `journalctl`, so that you can notice why your system's broken:


			```bash
			`logger "Installed new dnsmasq"`
			`sudo journalctl -f`
			```