How to Check Server Logs from Your iPhone

Most on-call questions are answered by thirty lines of log. You do not need a laptop for that: with WebSSH you can open the log on your iPhone, follow it live, copy the interesting lines and act on them from the same screen.

This guide covers the commands, how to make log output readable on a phone, and how to turn your usual log checks into one-tap snippets.

The Commands You Need

System and service logs (systemd):

journalctl -u nginx -n 50 --no-pager          # last 50 lines of a service
journalctl -u nginx -f                        # follow it live
journalctl -p err --since "10 min ago" --no-pager   # errors only, last 10 minutes
journalctl -b -p warning --no-pager           # warnings and worse since boot

Plain log files:

tail -n 100 /var/log/syslog
tail -f /var/log/nginx/error.log
grep -i error /var/log/nginx/error.log | tail -n 20

Docker:

docker logs --tail 100 myapp
docker logs -f --since 15m myapp
docker compose -f /srv/myapp/compose.yml logs -f --tail 50

Press Ctrl-C to stop following. On the iPhone keyboard, Ctrl is on the WebSSH accessory row above the keys.

Make Logs Readable on a Phone Screen

Log lines are long and a phone is narrow. A few habits help a lot:

Rotate the iPhone. Landscape roughly doubles the columns.
Lower the font size for log sessions: see terminal font size.
Drop what you do not need. journalctl -o cat removes timestamps and hostnames; --no-hostname keeps the time but drops the host.
Cut long lines when you only need the start: tail -f app.log | cut -c1-120.
Pretty-print JSON logs with jq: docker logs --tail 50 api | jq -r '.level + " " + .msg'.
Filter before you read. grep -iE 'error|fail|timeout' beats scrolling.

Scroll While Following

tail -f and journalctl -f scroll away as new lines arrive. If you need to read back while still following, use less:

less +F /var/log/nginx/error.log

Press Ctrl-C to stop and scroll freely, Shift-F to resume following, q to quit.

Follow in One Tab, Act in Another

Keep the log running in one terminal and use a second one for commands. On iPhone, tap the multiple windows icon at the top left of the terminal and choose New tab; switch back and forth with the same icon. See Multiple connections.

When you find the cause, the fix is usually one of these: restart the service or edit its config file.

A few lines: select the text in the terminal with the standard iOS gesture and tap Copy.
A whole stretch of output: open the ⋯ menu, choose Copy, then Show Scrollback Buffer. The full buffer opens in a separate view where selecting large blocks is easy.

See copying text from the terminal.

Turn Your Log Checks into Snippets

A snippet with dynamic variables asks which log and how many lines every time you tap it:

tail -n {{{ LINES : 100 }}} -f {{{ LOG : /var/log/syslog : /var/log/auth.log : /var/log/nginx/error.log }}}

A second one for services:

journalctl -u {{{ UNIT : nginx : postgresql : docker }}} -n {{{ LINES : 50 }}} --no-pager

And a one-tap Ctrl-C to stop following, using a key token: a snippet whose content is just <ctrl-c>.

Watching Logs for Longer Than a Minute

Two iOS behaviours matter here:

The screen locks. Set iOS Settings → WebSSH → Device Awake Strategy to Keep Device Awake if Session Active so the phone stays on while a terminal is open.
Backgrounding ends the session. If you switch to another app, iOS suspends WebSSH after about 30 seconds and the SSH connection closes. Run tail -f inside tmux so it keeps running server-side, and reattach when you come back.

For a live number rather than a stream, the Terminal State Bar can run a short command on the server at a fixed interval and display the result, for example the count of errors in the last ten minutes.

Frequently Asked Questions

How do I stop tail -f on an iPhone?

Press Ctrl-C. In WebSSH the Ctrl key is on the accessory row above the on-screen keyboard. You can also create a snippet containing the key token to stop with a single tap.

Why does the log stop updating when I switch to another app?

iOS suspends apps about 30 seconds after they leave the foreground, which closes the SSH session. Run tail -f or journalctl -f inside tmux so it keeps running on the server, then reattach when you return to WebSSH.

How can I copy a long block of log output on iPhone?

Open the terminal's ⋯ menu, choose Copy, then Show Scrollback Buffer. The full buffer opens in a separate view where you can select and copy as much as you need.

How do I read logs on a small screen without wrapping?

Rotate the phone to landscape, reduce the terminal font size, and trim the output: journalctl -o cat drops timestamps, cut -c1-120 shortens lines, and grep filters before you read.

Last update: September 23, 2026