Oracle 19 - RMAN can't connect to database

I have troubles with starting RMAN and connecting to target database.

I start RMAN ($ORACLE_HOME & $ORACLE_SID env variables are set)

[oracle@MY_MACHINE /]$ /u01/app/oracle/product/19.0.0/dbhome_1/bin/rman

RMAN starts sucessfully...

Recovery Manager: Release 19.0.0.0.0
.
.

Then i try to execute this command to connect to the target database:

RMAN> Connect target /

But this fails with this error:

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
ORA-27140: attach to post/wait facility failed
ORA-27300: OS system dependent operation:invalid_egid failed with status: 1
ORA-27301: OS failure message: Operation not permitted
ORA-27302: failure occurred at: skgpwinit6
ORA-27303: additional information: startup egid = 54321 (oinstall), current egid = 54329 (asmadmin)

From my research I did, I found some resources that said the problem is usually wrong permissions on $ORACLE_HOME/bin/oracle binary. They should be set to chmod 6751.

I verified that the permissions on the binaries are correct and they seem to be.

[oracle@MY_MACHINE /]$ ls -lah /u01/app/oracle/product/19.0.0/dbhome_1/bin/oracle
-rwsr-s--x. 1 oracle asmadmin 421M Dec 23  2020 /u01/app/oracle/product/19.0.0/dbhome_1/bin/oracle

Do you have any other ideas what might be causing this error?

Thank you

Additional details

• Oracle Linux Server 7.9
• GRID + ASM installed
• Two Oracle homes:

[oracle@MY_MACHINE /]$ ls  /u01/app/oracle/product/19.0.0/
dbhome_1  grid

• Groups of the oracle user:

[oracle@MY_MACHINE /]$ groups
oinstall dba oper backupdba asmdba asmoper asmadmin

Asked by user255888 (13 )
Jul 20, 2022 at 10:15