Module rlm_sql became unblocked messages

[Alan DeKok]

On Apr 8, 2025, at 10:16 AM, Can Paçacı <pacaci at servisnet.com.tr> wrote:
> Sometimes occures "WARNING: Module rlm_sql became unblocked" in the "Received Accounting-Request"  on the FR server logs and dont sent back the "Sent Accounting-Response" packet to the NAS. But when I checked the db. radacct records, the acct. "Interim-Update" record was inserted into the radacct table.

  The issue is that the database is slow.  FreeRADIUS isn't the problem.  It's just logging the messages.

> But NAS sends the "Accounting-Request" packet again and again a duplicate error is logged because it has been entered into the db before.

  That's now how the default accounting queries work.  They are designed explicitly to be able to deal with retransmissions, duplicate packets, etc.

> I don't observe any slowdown in db. and server load is also quite low.

  No.

  The database is slow.  The message "Module rlm_sql became unblocked" means that the database is slow.  You need to fix this problem.

  Nothing you do to FreeRADIUS will fix the slow database.

> This creates unnecessary acct. traffic and causes radius server UP-DOWN on the NAS side then switch into secondary FR server.
> How can I solve this problem?

  Fix the database.

> FreeRADIUS Version 3.0.20 and db. PostgreSQL 12.8, db. server and radius server are on separate servers.

  You should upgrade FreeRADIUS, too.  But it won't fix the database.

  The only solution here is to find out why the database is slow.  Then, fix it.

  Don't say "but the database is fine".  It's not.  It's slow.  The FreeRADIUS message is VERY clear on this problem.

  Alan DeKok.