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yorrd

Member

Registered: 2013-07-21

Posts: 71

MongoDB can't create a user --> Failed to mlock

Hi,

I've got the latest version of mongodb from the repository installed after updating from 3.4 a week back. It starts and works just fine until today.

I was going to switch on access control for the first time and therefore create a user. When doing `createUser`, the server crashes. After rebooting, the user is not created.

The error looks as follows:

2018-01-15T08:06:14.360+0100 F -        [conn2] Fatal Assertion 28832 at src/mongo/base/secure_allocator.cpp 246
2018-01-15T08:06:14.360+0100 F -        [conn2] 

***aborting after fassert() failure

... and then a stack trace.

On the MongoDB issue tracker, I found https://jira.mongodb.org/browse/SERVER-29086, recommending to increase mlock limits. So I looked at my mlock limits and they are unlimited. More specifically, for the su and mongodb users, `ulimit` returns `unlimited`.

Am I missing something here? The error pretty clearly states that it can't mlock, however I don't see why that would be.

Thanks a lot for any ideas.

Last edited by yorrd (2018-01-15 07:20:02)

x33a

Forum Fellow

Registered: 2009-08-15

Posts: 4,587

Re: MongoDB can't create a user --> Failed to mlock

On the bug that you linked, it says to increase the memlock limits *as a workaround*. The bug that it further linked to has been fixed, so if this problem is still there, then either it's a different issue, or it's a regression. I suggest you report it upstream.