Author: sotech
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How to find number of cores in Ubuntu (or other versions of Linux)?
If you’re using a virtual server (whether online or your own physical machine) it can be handy sometimes to check how many CPU cores are available; here are two easy methods of doing this. The first: nproc This will return a single number, whether it be 1, 2, 4 or otherwise. For…
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Finding /var/log/auth.log in CentOS 6
This one is straight-forward – if you’re used to Debian and are in a CentOS system looking for /var/log/auth.log you’ll find it in: /var/log/secure Short and sweet!
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ZFS: Renaming a zpool
If you’ve imported a pool from another system and want to change the name or have just changed your mind, this is actually quite straightforward to do. Run the following (as root): zpool export [poolname] As an example, for a pool named tank which we wish to rename notankshere: zpool export tank Then run:…
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Western Digital Green drive resilver rates
We get asked fairly regularly about resilver rates for ZFS pools – these matter as it impacts on how quickly a vdev with faulty disks can rebuild data onto a fresh disk, as well as how quickly you can swap one disk for another. The longer it takes to rebuild the vdev after…
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New Wireless Access Point: TP-Link TL-WA701ND
We have a new wireless AP in-house for testing: It’s pretty inexpensive, but does it do what it says on the box? Stay tuned for a review 🙂
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Samba log showing error: failed to retrieve printer list
If you’re using Ubuntu and seeing the following error in your Samba log: Failed to retrieve printer list: NT_STATUS_UNSUCCESSFUL If you are a home user and using samba purely for file sharing from a server or NAS you’re probably not interested in sharing printers through it. If so, you can prevent this…
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How to see individual CPU core loads in Ubuntu
This is an interesting one – if you have the need to monitor your CPU usage individually across cores it’s actually quite easy with the top command. Simply run top and hit “1” – your output will go from: to: In this case the server is a hexcore (0-5 cores shown, 6…
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How to kill a process after a set period of time
Knowing how to limit how long a process will run for is quite useful, particularly when you have daily backup scripts and the like which may at times run more than 24 hours; having multiple processes attempting to synchronize the same files can waste time, bandwidth and CPU power needlessly. The command we will…
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How to easily find the full path of a command in Ubuntu
If you’re writing scripts or making cron jobs you will need to know the full path of the commands you’re using; rather than just being able to use “ls” you would have to use “/bin/ls” instead. You could use the find command here but there’s a quicker and more elegant way: which. Use it…