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Unix

A collection of 5 posts

Unix

How to compress a PDF file on MacOSX (& Linux)

Often (and especially when scanning documents with my printer) from MacOSX I would get unreasonable huge PDFs which are not suitable for emails. To strip them down without pain one can use ghostprint:...

  • Andrea Leofreddi
    Andrea Leofreddi
1 min read
Backup

Bacula mail changer script (aka poor man's autoloader)

I enjoy Bacula for automated home backups on DLT and DDS tape drives. Being used at home there’s no – obviously – big-dollar-company-manager to ask for an autoloader; and when the time of...

  • Andrea Leofreddi
    Andrea Leofreddi
3 min read
Linux

Nagios nrpe and sudo: NRPE: Unable to read output

On CentOS 5 (and RedHat EL as well), you can encounter the following behaviour when configuring an nrpe plugin with sudo: [andrea@feyd ~]$ /usr/lib/nagios/plugins/checknrpe -H 1.2.3.4 -c checkmd_raid NRPE: Unable to read output...

  • Andrea Leofreddi
    Andrea Leofreddi
1 min read
Linux

SSH X11 forwarding issue

Recently I’ve been in an awkward situation with ssh and X11 forwarding, where ssh using the classic or option wasn’t working (DISPLAY was not set): [andrea@duncan ~]$ ssh -Y root@thufir root@thufir's password: Last...

  • Andrea Leofreddi
    Andrea Leofreddi
1 min read
Solaris

seq equivalent

On platforms without (MacOSX, Solaris), you can emulate it using as follows (note the upper bound and the lower bound): For example: alia:~ andrea$ echo '[1+pd5>aq]sa0 1-lax' | dc 0 1 2 3...

  • Andrea Leofreddi
    Andrea Leofreddi
1 min read
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