Taking Yassine solution a step further.
On the Spectrum Protect Server side change to transitional :
UPDATE NODE <node_name> SESSIONSEC=TRANSITIONAL
To re-create the SSL certificates , we recommend performing the below steps:
1. Obtain the IBM Spectrum Protect server self-signed certificate (cert256.arm). The certificate file is stored on the server workstation in the server instance directory, for example, /opt/tivoli/tsm/server/bin/cert256.arm.
2. Copy this certificate into the Spectrum Protect client installation directory
3. Stop any IBM Spectrum Protect administrator and backup-archive clients that are running on the affected system.
4. From the Spectrum Protect client installation directory, remove the following files, if they exist:
dsmcert.crl
dsmcert.idx
dsmcert.kdb
dsmcert.rdb
dsmcert.sth
5. From the Spectrum Protect client installation directory , run the dsmcert command again to import the cert256.arm file with the correct server name. For example:
dsmcert -add -server SERVER1 -file cert256.arm (in this example SERVER1 is the name of the Spectrum Protect Server)
The dsmcert command writes new dsmcert.* files.
6. Run the dsmc q session command to check connectivity.
The above is from the following techdoc 6238326
Backup fails with "ANS1579E GSKit function gsk_secure_soc_init failed with 406: GSK_ERROR_IO"
Good Luck,
Sias