3 files changed, 43 insertions, 1 deletions
diff --git a/prompts/skills/f3s-storage/SKILL.md b/prompts/skills/f3s-storage/SKILL.md
index 865c2e3..9c49968 100644
--- a/prompts/skills/f3s-storage/SKILL.md
+++ b/prompts/skills/f3s-storage/SKILL.md
@@ -26,7 +26,7 @@ Note: original plan was HAST, replaced by **zrepl** (ZFS send/receive) — more
 - [NFS over stunnel](references/nfs.md) — NFS server, mutual-TLS stunnel, Rocky client config, `/etc/fstab`
 - [nfs-mount-monitor](references/nfs-mount-monitor.md) — systemd watchdog on r-nodes (mount/stat/write probes, fail counter, cordon-and-reboot escalation)
 - [Troubleshooting](references/troubleshooting.md) — NFS issues, ZFS pool SUSPENDED recovery, **thermal** troubleshooting (Beelink S12 Pro)
-- [Backups & Local-Path](references/backups.md) — S3 Glacier Deep Archive, when to use `local-path` instead of NFS
+- [Backups & Local-Path](references/backups.md) — S3 Glacier Deep Archive, AWS CLI setup on a FreeBSD host (pkg + `/root/.aws` symlink to `/opt/snonux/secrets/aws.credentials`), when to use `local-path` instead of NFS
 
 ## Storage Summary
 
diff --git a/prompts/skills/f3s-storage/references/backups.md b/prompts/skills/f3s-storage/references/backups.md
index 99fd425..2181ebc 100644
--- a/prompts/skills/f3s-storage/references/backups.md
+++ b/prompts/skills/f3s-storage/references/backups.md
@@ -4,6 +4,41 @@
 
 Encrypted incremental ZFS snapshots from `zdata` pool backed up daily to **AWS S3 Glacier Deep Archive** via cron. Scripts adapted from FreeBSD Home NAS setup. Also performs periodic zpool scrubbing.
 
+The **`zusb` quarterly backup** (`/opt/snonux/bin/backup/backup`, which travels on the `zusb` pool — see [USB Key Mounting](usb-keys.md) → "Removable backup pool (`zusb`)") also uploads to the same S3 Glacier Deep Archive bucket (`s3://org-buetow-backup/<host>/`). Both workflows need the AWS CLI on the host that runs them.
+
+### AWS CLI setup on a FreeBSD host
+
+Install the `awscli` package. The Python flavor depends on the FreeBSD version:
+
+```sh
+# FreeBSD 14.x (e.g. t450)
+#   py39-awscli-1.29.81
+# FreeBSD 15.x (e.g. f1, f-hosts)
+#   py312-awscli-1.42.44
+sudo pkg install -y py312-awscli   # adjust py3XX to what pkg search -q awscli shows
+```
+
+Wire `/root/.aws` (the backup script runs `aws` as root). The **credentials ride on the `zusb` pool** at `/opt/snonux/secrets/aws.credentials` (INI: `[default]` + `aws_access_key_id` + `aws_secret_access_key`), so on any host that has `zusb` imported (i.e. `/opt` mounted) you only need the config file and a symlink — the secret is not duplicated on host disks and is not in git:
+
+```sh
+sudo mkdir -p /root/.aws && sudo chmod 700 /root/.aws
+printf '[default]\nregion = eu-central-1\n' | sudo tee /root/.aws/config >/dev/null
+sudo chmod 600 /root/.aws/config
+sudo ln -sf /opt/snonux/secrets/aws.credentials /root/.aws/credentials
+```
+
+Because the credentials are a symlink into `/opt` (`zusb/data/opt`), `aws` only resolves them while `zusb` is imported on that host. That is fine for the quarterly backup workflow (load `zusb` → run backup → export `zusb`); it is **not** suitable for the `zdata` daily-cron S3 backup on an f-host that does not normally have `zusb` imported — that host would need its own credentials copy (out of scope here).
+
+Verify (read-only):
+
+```sh
+aws --version
+aws sts get-caller-identity        # expect Arn arn:aws:iam::634617747016:user/org-buetow-backup-user
+aws s3 ls s3://org-buetow-backup/   # expect the per-host prefixes (e.g. t450/)
+```
+
+Installed 2026-07-20 on f1 (`py312-awscli-1.42.44`), matching the t450 setup (`py39-awscli-1.29.81`, same `/root/.aws/config` region and the same credentials symlink).
+
 ## Local-Path Storage for SQLite Workloads
 
 Some k3s workloads use `local-path` (k3s default storageClass) instead of NFS for
diff --git a/prompts/skills/f3s-storage/references/usb-keys.md b/prompts/skills/f3s-storage/references/usb-keys.md
index 07b7414..9c40333 100644
--- a/prompts/skills/f3s-storage/references/usb-keys.md
+++ b/prompts/skills/f3s-storage/references/usb-keys.md
@@ -141,3 +141,10 @@ that old passphrase key is now obsolete for `zusb`.
 Scripts and deployment docs live in the conf repo at
 `f3s/freebsd-hosts/zusb/` (`zusb-load`, `zusb-unload`, `README.md`). The raw
 key itself is **not** in git — it is copied stick-to-stick like the other keys.
+
+The backup workflow itself is driven by `/opt/snonux/bin/backup/backup` (which
+travels on the pool under `zusb/data/opt`); its S3 sync leg needs the AWS CLI
+installed on the hosting f-host — see [Backups & Local-Path](backups.md) →
+"AWS CLI setup on a FreeBSD host". The S3 credentials also ride on the pool at
+`/opt/snonux/secrets/aws.credentials` and are wired in via a
+`/root/.aws/credentials` symlink, so no secret material lives on host disks.