## TL;DR
Instant Recovery failed to mount means Veeam could not present the backup as a datastore to the hypervisor. The mount server, its NFS or iSCSI path, and hypervisor permissions all have to line up. Check the mount server service, datastore creation rights, and network path, then retry the mount before falling back to a full restore.

```text
veeam instant recovery failed to mount
```

## Use this when
- Instant Recovery or Instant VM Recovery stops at the mount step.
- The hypervisor shows a datastore creation or NFS mount error from the mount server.
- Other restores from the same repository work, but instant mounts fail.

## Not for this skill when
- A standard restore fails reading blocks. That is a chain or repository read problem.
- The restored VM boots but fails inside the guest. That is a guest problem after a successful mount.

## Steps
1. Identify the mount server for the repository and confirm its Veeam services are running and it can read the backup files. Verify: mount server services are up and files are readable
2. In the hypervisor, check the error when the NFS datastore from the mount server is added and note any version or export restriction. Verify: the exact hypervisor mount error is recorded
3. Confirm the mount server exports allow the hypervisor hosts and that required ports between hosts and mount server are open. Verify: a manual mount test from a host succeeds
4. Check the account used has rights to create datastores and register VMs on the target host or cluster. Verify: a test datastore can be created and removed
5. Retry Instant Recovery and watch the VM register and power on from the mounted datastore. Verify: the VM runs from backup storage

## Variant phrasings
### veeam instant vm recovery mount failed
The Instant VM Recovery phrasing.
### veeam instant recovery nfs datastore failed
The NFS datastore variant.
### veeam failed to mount backup datastore
The plain mount wording.

Compatibility: Veeam Backup and Replication 11 and 12 Instant Recovery to VMware vSphere 7 and 8 and Hyper-V, with Windows or Linux mount servers.

## Why it happens
Instant Recovery publishes backup files through a virtual filesystem on the mount server, usually NFS v3 to VMware hosts. Any break in that chain, a stopped mount service, an export limited to the wrong hosts, a firewall change, or reduced hypervisor rights, surfaces as a generic mount failure even though the backup itself is healthy.

## Edge cases / pitfalls
- A mount server overloaded by other jobs can time out mounts. Check its load during the failure window.
- After a repository move, mounts can still point at the old mount server. Re-check repository settings.
- Migrating the running VM to production storage with Storage vMotion completes the recovery. A mounted VM left running on backup storage is at risk.

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_OPwe4C1mUyega7uwmHG1NA