Environment :
BP_Master : NBU 3.4.1 DC Master, patch 4a + SSO
Exc_Node1 (A) & Node2 (P) : NBU 3.4.1 D Media, patch 4a + NBU exchange agent
(active-passive clustered) + SSO
Exc_Node3 (A) & Node4 (P) : NBU 3.4.1 D Media, patch 4a + NBU exchange agent
(active-passive clustered) + SSO
SSO tape library : 5 drives, joint with above servers

i face 1 problem that got one time, Exc_Node3 (active) faced some problems,
and in its OS level detected only 4 drives. Then onward I faced issue with
backup, such as
1. backup slow!
2. BP_Master & Exc_Node1 seem also facing tape backup problem, some even
error.. fail the job.

Any ideas with Automated tape cleaning on the SSO tape driver?

Please suggest me solution, as well as any documents to read?

Thanks