# RST-4402: restore of /srv/atlas came back larger

**Requested** 2026-05-21 · **Tape** LTO-6, barcode `A0071L6`, written
2019-06-17 · **Requested by** platform, for a licence audit

## Why we restored it

Legal needed the `/srv/atlas` tree as it stood in June 2019 to answer a
question about which build of a library was in the image. Routine. The tape is
one of forty-one in the 2019 offsite set, all written by the same appliance, all
verified on write and re-verified in the 2022 audit.

## What came back

| | On the manifest | Restored |
| --- | --- | --- |
| Files | 118,406 | 119,847 |
| Directories | 3,912 | 3,913 |
| Bytes | 44,109,882,113 | 44,116,551,204 |
| Checksum (manifest) | `c41f…8ae0` | `c41f…8ae0` |

The manifest checksum matched. The manifest checksum is computed over the file
list, and the file list is on the tape, and the file list has 118,406 entries.
The restore wrote 119,847 files. Both numbers are correct; they disagree.

The extra directory is `/srv/atlas/held/`. It contains 1,441 files, which is the
difference. Nothing on the manifest mentions it. Nothing in the 2019 source
control mentions it. `atlas` was decommissioned in 2021 and its owners have all
left.

## What is in it

Every file in `held/` is named for a date and has the same shape: a plain-text
recursive listing of `/srv/atlas`, with sizes and mtimes, as it stood on that
date.

```
$ ls held/ | head -5
2015-08-30.list
2015-08-31.list
2015-09-01.list
2015-09-02.list
2015-09-03.list
$ ls held/ | tail -3
2019-06-15.list
2019-06-16.list
2019-06-20.list
$ ls held/ | wc -l
1441
```

1,441 dates, consecutive from 2015-08-30 to 2019-06-16, and then
`2019-06-20.list`. The tape was written on 2019-06-17.

The listings are accurate. We spot-checked eleven of them against the four
independent backups we still hold from 2016, 2017 and 2018, and every path,
size and mtime matched.

Every listing includes `held/` itself, with a file count for that date. The
counts increase by one per day, exactly, from `1` on 2015-08-30.

`2019-06-20.list` reports `held/` as containing 1,441 files.

## Disposition

The tree has been copied to `/srv/audit/rst-4402/` and the tape returned to the
vault. Legal got their answer from `lib/`, which is what they asked for, and the
ticket can be closed on that basis.

I have not opened `2019-06-20.list` beyond `held/`. I am aware that this is not
a technical decision.

Related: [[stories/mtime]], [[stories/inventory-diff]]. On why a stored artefact
and a claim about it are two different objects, [[machinery/anatomy-of-a-page]].