Instructions on how to troubleshoot read/write issues with tape devices.
Introduction
When backing up to tape, you may encounter issues with device detection or read/write operations. This article provides instructions on how to troubleshoot such issues and what information to collect for investigation.
About
Tape devices use magnetic tape media to store information and can be divided into 3 types:
- Standalone tape drives. Here one tape cartridge can be inserted into the device and used. To write or read data from other tape cartridge, the previous tape has to be ejected and taken out from the drive first.
- Tape library is a device that apart from a tape drive (one or more) has also additional slots to store tape cartridges. Tapes can be moved between slots and drives via the device or third-party software interface. A slot that allows inserting new tapes and ejecting tapes is called mail slot. Tapes in tape libraries usually have unique barcodes which can be optically read by the reader during inventory. The barcode duplicates the information stored in tags placed in the beginning of the tape data.
- Virtual tape library (VTL) is a storage virtualization technology, that allows the representation of a storage device as a tape library or a tape drive. Usually is it used to represent a hard disk storage device as a tape library, in a special case an RDX device.
When speaking of tape types, LTO is a major standard and the version of the LTO tape cartridge defines its characteristics including capacity. Modern generation LTO-7 and LTO-8 come with HDD competitive read/write speed of 300 and 360 MB/s and capacity of 6TB and 12TB GB respectively.
Tapes are storage media that can only be read sequentially as opposed to HDDs, and per ABR tape vault format we can only add something to the free end of the tape, but we cannot re-write a part of the tape and place new information keeping some piece of previous information. Tape will always be overwritten completely.
Acronis Cyber Backup software can write to the tapes locally using Acronis Cyber Backup Agent (when the backup operation is performed directly to the tape device) or via Acronis Storage Node when the backup operation is performed from remotely installed agent. If Acronis Storage Node is installed then the write to tape operation can be performed only by Acronis Storage Node.
Troubleshooting
Follow step-by-step instructions below to troubleshoot the issue. Complete prerequisites step before proceeding to error troubleshooting step.