expected a BackupNum value of 1 for first manifest but got %

Error message

expected a BackupNum value of 1 for first manifest but got %d

What it means

verifyManifests checks a list of backup manifests before a restore or verification. Backup manifests are stored newest-first conceptually: the last manifest in the slice must have BackupNum == 1 (the oldest, full backup). This error is thrown when the manifest expected to be the oldest backup has a BackupNum other than 1, meaning the manifest sequence is incomplete, reordered, or corrupted.

Source

Thrown at worker/backup_manifest.go:31

	"sort"
	"strings"
	"time"

	"github.com/golang/glog"
	"github.com/pkg/errors"

	"github.com/dgraph-io/dgraph/v25/protos/pb"
	"github.com/dgraph-io/dgraph/v25/x"
)

func verifyManifests(manifests []*Manifest) error {
	if len(manifests) == 0 {
		return nil
	}

	lastIndex := len(manifests) - 1
	if manifests[lastIndex].BackupNum != 1 {
		return errors.Errorf("expected a BackupNum value of 1 for first manifest but got %d",
			manifests[lastIndex].BackupNum)
	}

	backupId := manifests[lastIndex].BackupId
	backupNum := uint64(len(manifests))
	for _, manifest := range manifests {
		if manifest.BackupId != backupId {
			return errors.Errorf("found a manifest with backup ID %s but expected %s",
				manifest.BackupId, backupId)
		}

		if manifest.BackupNum != backupNum {
			return errors.Errorf("found a manifest with backup number %d but expected %d",
				manifest.BackupNum, backupNum)
		}
		backupNum--
	}

View on GitHub (pinned to 759e242be6)

Solutions

Ensure all manifest files from the original backup are present and unmodified in the backup location.
Do not delete or reorder manifest-N files; the full chain ending with BackupNum 1 must exist.
Re-run a complete backup into a fresh location and restore from that.
Verify the URI handler is listing paths from the correct backup root (no partial path prefix).

Example fix

// before: only some manifests copied
// s3://backup/dgraph.1, dgraph.2 present, dgraph (num 1) missing
// after: copy the entire backup set
aws s3 sync s3://backup/ s3://newbucket/dgraph-backup/ --exact-timestamps

Defensive patterns

Strategy: validation

Validate before calling

manifests, _ := listManifests(uri)
if len(manifests) > 0 && manifests[len(manifests)-1].BackupNum != 1 {
    return fmt.Errorf("backup set incomplete: oldest manifest BackupNum=%d, want 1", manifests[len(manifests)-1].BackupNum)
}

Type guard

func isOldestFirst(m []Manifest) bool {
    return len(m) > 0 && m[len(m)-1].BackupNum == 1
}

Prevention

Never delete or reorder manifest files in a backup location
Copy the entire backup set atomically (sync whole prefix)
Use one destination directory per backup run

When it happens

Trigger: Calling verifyRequest/verifyManifests with a manifests slice whose last element (in storage order) has BackupNum != 1 — e.g. after manually copying/deleting manifest files from the backup location, uploading only part of a backup, or listing manifests in the wrong order.

Common situations: Partial backups restored into a new bucket; users deleting what look like 'old' manifest files; manually renamed/copied backup directories; backup storage truncated by lifecycle policies.

Related errors

AI-assisted analysis of dgraph-io/dgraph@759e242be6 (2026-09-01). Data as JSON: /api/errors/1ff98c337dc3842e. Report an issue: GitHub.