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What is the maximum number of users accounts I can have on Linux?

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up vote 13 down vote accepted

65.000 for 2.4 kernels, and 4 billion for 2.6 kernels.

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When are they gonna fix that? What if I want to make one account for every person in the world? – Johanna Larsson Nov 12 '10 at 13:31
Fun fact: assuming an the average entry in /etc/passwd is 75 bytes, 4 billion users would give you an /etc/passwd that's just a shade under 300GB. :-) – ThatGraemeGuy Nov 12 '10 at 14:17
@shintoist: Because things are made based on what's probable, not what's possible. It's possible that you would want to create a user account in a single Linux system for every person in the world, but it's not probable that you'd actually do that. – joeqwerty Nov 12 '10 at 14:39
@joeqwert Yes, because I was being serious... – Johanna Larsson Nov 12 '10 at 14:48
Do you have any source of these numbers? – Fabian Jakobs Nov 14 '10 at 21:03

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