Questions tagged [tail]
Watching updates at the end of a file, with or without the tail utility
432 questions
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Is there anything like `tail -f` but that can follow multiple files and show which file each line came from? [duplicate]
I'm trying to monitor multiple log files simultaneously, but when I use:
tail -f /var/log/app1.log /var/log/app2.log
I get mixed output and can't easily tell which file each line originated from. What ...
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Never exit "less +F" if the tailed file disappears?
Under ubunu 22.04, I'm using the standard less pager.
When running less +F against a log file, I never want less +F to automatically exit if the log file disappears. Instead, I want the current view ...
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What is the `-0` flag in `tail`? [duplicate]
The Logstash documentation said about the input file plugin that it
Stream events from files, normally by tailing them in a manner similar to tail -0F but optionally reading them from the beginning.
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Why does `tail -c 4097 /dev/zero` exit immediately instead of blocking?
I observe that, on Ubuntu 24.04.2 with coreutils version 9.4-3ubuntu6, running:
$ tail -c 4097 /dev/zero
$ echo $?
0
exits immediately with a status code of 0. I expected the command to block ...
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Does "less" have "--retry" option like "tail"?
I'm using less to continuously trace Squid log file (as well as UFW log) with this command:
less --follow-name -K +F /var/log/squid/access.log
And at the time of rotation of Squid log less quits. I ...
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1
answer
672
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"Tail -f" on symlink that points to a file on another drive has interval stops, but not when tailing the original file
I'm encountering a strange behaviour with tail -f, when tailing a symlink on an Ubuntu machine.
Apparently, tail uses the default update interval of 1 second. If tailing the original file, it seems to ...
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Run a few identical process and then kill one of them
Problem:
Need to run several process, especially it will be “tail -f log.log >> wrile_log.log” proces to collect log.
Commands can be run at the different time for same log file. This is not ...
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237
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How to know when a following tail moves from old file to the new one
So, I am working with tail -F ( or tail --follow=filename). Now it works as advertised and when a rollover occurs it will move to the new file.
This is great and helps me keep track of my logs. The ...
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How to tail continuously a log file that is being deleted and recreated?
I need to extract information from a log file that is deleted and recreated every time a program runs. After detecting that the file exists (again), I would like to tail it for a certain regexp.
The ...
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How can I save the output of tail to my clipboard or somewhere on a SSH session where there is only a unidirectional connection and server is limited?
I have to report some logs from some of the servers in our infrastructure which I have limited permissions on. Every time I copy 1000 lines of logs and paste it into Slack, I can't do scp from the ...
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How do I read the last lines of a huge log file?
I have a log of 55GB in size.
I tried:
cat logfile.log | tail
But this approach takes a lot of time. Is there any way to read huge files faster or any other approach?
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314
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Can't clear / scroll-back buffer when using tail -f alacritty?
When I use tail with the -f option, I can not find anyway to clear the screen. It just shows a ^L. Same problem when following live logs with docker.
While I'm just in the shell, the cmd-k works fine.
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pfSense (FreeBSD) - tail -f not showing entire log when filtering with cut or sed [duplicate]
I have a strange problem when trying to display logs on pfSense (and I can reproduce the same problem on Ubuntu server also).
The problem is this (with examples):
I'm trying to display a running dhcp ...
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666
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How to tail -f multiple files and grep each file individually in single output?
I have several log files (related to my webserver aka various error_log, access_log, etc.) that I want to monitor in real time, ie to see recent updates AND I need to filter each file individually ...
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Linux "watch" command showing last 30 lines of nft list ruleset [duplicate]
I want to constantly see last 30 lines of code "nfc list ruleset" in Debian Bash. Something like this:
watch -n 1 nft list ruleset | tail -n 30
But above code doesn't show last 30 lines of &...
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