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I was writing a udev rule that makes use of the ID_PATH, just to make the device persistent against the port it's inserted in.

So here is what I have


Initially, the file is called 52-foo.rules, and it doesn't work. I renamed it to 81-foo.rules and it works fine.

It's like the ENV{} values are only valid if the number are large enough. Could somebody explain why this is the case?


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Perhaps your rule is being overwritten by another rule. Since higher numbered rules run last, it doesnt get overwritten when you use a higher number.

< 60  most user rules; if you want to prevent an assignment being
overriden by default rules, use the := operator.

these cannot access persistent information such as that from

< 70  rules that run helpers such as vol_id to populate the udev db

< 90  rules that run other programs (often using information in the
udev db)

>=90  rules that should run last

Check this

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