Hosting Operations
Read-onlyFind Cron Jobs With No Log Trail
Cron jobs without redirects, mail, or logger calls can fail without leaving an obvious trail.
Command
crontab -l | awk 'NF && $1 !~ /^#/ && $0 !~ /(>>|2>|logger|mail)/ {print}'Before you run this
System impact: Read-only. Low when scoped to the shown target.
When not to use it: Do not treat this as proof the job is broken; it is a prompt to inspect observability.
Expected output
Cron lines that lack obvious logging or notification patterns.
System impact
Read-only. Nothing changes. The command prints active lines that do not appear to capture output.
Recovery / rollback: no state is changed.
When to use it
Use before relying on cron for backups, reports, billing, imports, or cleanup.
When not to use it
Do not treat this as proof the job is broken; it is a prompt to inspect observability.
Watch this command run
Command transcript
This sanitized transcript shows the commands and output shape without exposing host details.
$ crontab -l
# user crontab for demo
SHELL=/bin/bash
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
5 * * * * /usr/local/bin/check-disk >> /var/log/cron-disk.log 2>&1
17 2 * * * /usr/local/bin/backup-db
0 4 * * 0 /usr/local/bin/report-weekly | /usr/bin/mail -s report ops@example.com$ crontab -l | awk 'NF && $1 !~ /^#/ && $0 !~ /(>>|2>|logger|mail)/ {print}'
SHELL=/bin/bash
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
17 2 * * * /usr/local/bin/backup-dbView commands shown
These are the commands shown in the sanitized transcript.
Commands shown
crontab -lcrontab -l | awk 'NF && $1 !~ /^#/ && $0 !~ /(>>|2>|logger|mail)/ {print}'
next steps
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Study mapping
Use this as independent command practice: read the notes, predict the output, then compare it with the example before using a real shell.
Useful for
- LPIC-1 style command-line practice
- LFCS style performance tasks
- Linux+ style troubleshooting review
Independent study support only. No affiliation, endorsement, exam dumps, or real exam questions.