Proxmox has released Proxmox Backup Server 4.2, rebasing its enterprise backup platform on Debian 13.4 "Trixie" with Linux kernel 7.0 and ZFS 2.4. The headline additions target a persistent pain point for administrators managing distributed backup infrastructure: sync jobs can now encrypt snapshots on the fly before pushing them to remote servers, and pull jobs can decrypt data from encrypted remote datastores. All encryption keys, including those for tape, are now managed from a single centralized panel.
Sync performance gets a meaningful boost as well. A new worker-threads property allows sync jobs to process multiple backup groups in parallel, which should significantly improve throughput on high-latency links and work around HTTP/2 connection bottlenecks. On the organizational side, backup groups and namespaces can now be moved within a datastore without breaking consistency, thanks to per-group locking during the operation.
S3-compatible object stores are now officially supported as a backup storage backend, complete with request counting and traffic statistics visualized in the datastore summary. That makes it straightforward to monitor usage and catch unexpected traffic spikes early, a practical addition for anyone offloading backups to cloud-adjacent storage.
Proxmox Backup Server 4.2 is available immediately as an ISO download or as an in-place upgrade via APT from older versions. The entire solution ships under the GNU AGPLv3. Enterprise support subscriptions, which include access to the stable Enterprise Repository and certified technical support, start at $610 (€560) per server per year with unlimited backup storage and clients.
