I am Dale Hayter, a Microsoft and VMware certified Technical Consultant.

My blog has been built up over the years from my experience of working on an IT helpdesk and also from being out on-site.

Veeam Client Error : Failed to decompress LZ4 block

I have been using Veeam for years and it is the first time I have come across this error. One of our backup jobs is failing with the error :-

Error: Client Error: Failed to decompress LZ4 block: Incorrect decompression result or length (result: '-48198', expected length: '1048576').

For the moment I have logged a support case with Veeam. I’ll update this post as the case progresses.

Update 1 :

Veeam believe the metadata for the job to be corrupt. Asked me to run an active full. Same error. Back to Veeam

Update 2 :

Veeam said in 99% of cases this error is due to some storage glitch. They were not able to elaborate on this. “Veeam just writes backup files on to storage and performs archive crc check before job starts and at the end of the job”.

The recommended fix was to create a new job from scratch and keep the old backup files in case we need to restore something. Since this was a relatively new setup we decided to just delete the old backups.

On inspection of the storage I could see no issues. Its basically a physical server with a couple of disks in a RAID5. The only warnings were for 2 drives with older drive firmwares. We updated these in order to eliminate these if it reoccurs.