Michael,
What requirements make you ask for VTL?
VTLs regulary offer disk based storage for fast access without load / seek / unload - times, then they might offer advanced functions as compression, deduplication, replication, snapshots.
While some VTLs provide network file services, mot still offer SAS or FCP interfaces - do you really need those?
A sometimes viable alternative is Object Storage, mostly some type of amazon developed S3 protocol server available over TCP/IP only.
Perhaps you already use BRMS, so you could check wether the nowadays included "Cloud Storage Solutions" license of BRMS with a S3 backup target is a sensible alternative to virtualized tapes. Here, "cloud storage" is a synonym for the S3 protocol.
S3 storage servers are available in many on- or off-premises storage solutions, from SaaS to HW appliances - you can even roll your own from open source software.
IBM offers S3 protocol servers in IBM Storage Scale, IBM Storage Ceph and IBM Cloud Object Storage.
Details explained here: Using BRMS with Cloud Storage Solutions for i - IBM Documentation
and BRMS with Cloud Storage Solutions for i considerations and requirements - IBM Documentation
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Ilja Donnellan
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