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1 Problem: Today I encountered a strange behavior when trying to benchmark SSD's with a Raspberry PI and having two SSD's with the same label.

2 Setup: My setup is like this: My Raspi runs Ubuntu 2004 - the root file system is on a Samsung T5. On boot the root file system is identified by its label, so LABEL=rootfs. I tried to benchmark another Samsung T5 (exact same model), that coincidentally had a partition label rootfs as well. But plugging that SSD into the USB port renders the system useless. Basically every command is not found, and if using an absolute path the system complains about IO errors. Therefor I assume the kernel losses access to the root file system somehow.

3 Solution: Relabeling the partition with e2label /dev/sdb dummylabel fixes the issue. A restart is required. Unplugging the SSD doesn't help.

4 Question: Can anyone give me helpful advice or keywords where to look for more information that explains this behavior and gives an understanding of how devices get addressed in Linux. Or more in general, what solution finding process could I use to understand this. Book proposals are welcome. I'm not interested in every little detail but in enough understanding of the OS to be able to identify the cause of problems by myself and being able to read up on details if required.

Thanks for your time.

Citizen
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Andrino
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1 Answers1

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There are various persistent naming methods. You were mounting device by label. As an alternative you can use drive uuid. Check for more info: https://wiki.archlinux.org/index.php/Persistent_block_device_naming#by-partlabel RHEL storage administration guide should be helpful as well: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/storage_administration_guide/index The following book helped me as well: http://linux-training.be/linuxsto.pdf

Stuka
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