lock manager error

Olivier Mercier

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Dec 4, 2025, 4:43:14 AM (12 days ago) Dec 4

to firebird-support

Hello,

FireBird 3.0 classic 32bits, around 100 users, one database (64 go), client-server application.

Very good server (Intel Xeon Gold 6242 processors, 32 go RAM) under Windows Server 2022.

Today, under medium load, firebird refused connections, with this error in the firebird.log:

SVLIBDD01 Wed Dec 03 18:48:14 2025
Authentication error
cannot attach to password database
Error in isc_attach_database() API call when working with legacy security database
lock manager error
inconsistent lock table type/version; found 0/0:0, expected 255/1:18

The server has been rebooted in order to accept new connections.

Do you have an Idea of what happened, and how can i manage to avoid this situation ?

The firebid.conf in use is attached to the conversation.

Thanks in advance,

Olivier Mercier

TITE-LIVE

Firebird.furet.conf

Vlad Khorsun

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Dec 4, 2025, 6:00:55 AM (12 days ago) Dec 4

to firebird-support

FireBird 3.0 classic 32bits, around 100 users, one database (64 go), client-server application.

What is exact Firebird version ?

Very good server (Intel Xeon Gold 6242 processors, 32 go RAM) under Windows Server 2022.

Today, under medium load, firebird refused connections, with this error in the firebird.log:

SVLIBDD01 Wed Dec 03 18:48:14 2025
Authentication error
cannot attach to password database
Error in isc_attach_database() API call when working with legacy security database
lock manager error
inconsistent lock table type/version; found 0/0:0, expected 255/1:18

The server has been rebooted in order to accept new connections.

Do you have an Idea of what happened, and how can i manage to avoid this situation ?

Lock table (a whole or just a header) was zeroed by some reason.
A quick guess : anyone changes/deletes files in lock directory (%programdata%\firebird by default) manually ?

Too "smart" antivurus ?

Regards,

Vlad

Olivier Mercier

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Dec 4, 2025, 7:18:28 AM (12 days ago) Dec 4

to firebird-support

Thanks Vlad,

Version is FB 3.0.13

Thanks for the suggestion of Antivirus ! I will investigate in this direction (nobody can access the server in order to delete the files in the lock directory)