---
title: "Stack Labels"
description: "Per-node tags that group your stacks by purpose, surface them under collapsible headers in the sidebar, and enable cross-stack bulk actions across the fleet."
---
A **Stack Label** is a per-node tag (name plus color) applied to any stack. A labeled stack groups under that label's header in the sidebar instead of the flat list, and Fleet View can filter the overview by tag. Admins also get two label-driven fleet actions (stop every stack labeled `prod` across every node, or add a label to stacks across nodes in one shot) plus one-click shortcuts for muting a label's notifications.
Stack Labels are a different feature from **Compose Labels** (the raw `labels:` key-value metadata Docker Compose services declare) and from **Node Labels** (used for Blueprint placement). See [Docker Label Audit](/features/docker-label-audit) for the former; Stack Labels never read or write Compose-level labels.
## What problem this solves
A flat sidebar of fifteen same-level stacks forces a scan of every name. With Stack Labels:
- **Stacks group by purpose, not by alphabet.** Each label becomes a collapsible section header, sorted by stack count, so the busy buckets (your media stack, your network stack) sit at the top and rarely-touched ones can be folded away.
- **Bulk operations stop being copy-paste.** Stop every `prod` stack across the fleet from one card. Re-tag eight stacks at once when a service moves between concerns. No scripting, no per-stack menu hunt.
- **Alert noise can be silenced per group.** Mute a label's notifications (all of them, external channels only, or just low-priority ones) from the same places you manage the label, without hand-writing a mute rule.
## Anatomy of a label
| Field | Rule |
|---|---|
| **Name** | 1 to 30 characters. Letters, digits, spaces, and hyphens only (`^[a-zA-Z0-9 -]+$`). Case-sensitive and unique per node. |
| **Color** | One of ten swatches: teal, blue, purple, rose, amber, green, orange, pink, cyan, slate. The color drives the bullet on the group header, the dot in the Settings panel and the Fleet View Stack drill-down, and the swatch in the Fleet View **Tags** filter. |
| **Scope** | Per-node. The same name can exist on two different nodes with two different colors; the fleet-stop card matches by name across nodes. |
| **Limit** | 50 labels per node. The **New label** button switches to **Limit reached** when you hit the cap. |
## Where labels appear
### Sidebar grouping
The stack list is split into one collapsible section per label. Group headers render in uppercase mono with a count chip on the right (`MEDIA 6`). Order is fixed: a `★ PINNED` group first if any stacks are pinned, then label groups sorted by stack count descending and by label name ascending, then `UNLABELED` last for stacks that carry no label. A stack tagged with two labels appears in both groups. Search and the **All / Up / Down / Updates** filter chips above the list operate on rows inside whichever groups are expanded.
Stack rows themselves show only the status pill and name; they don't render a per-row label swatch. To see or change which labels a stack carries, right-click the row (or use its kebab) to open the **Labels** submenu, or check the Settings Labels panel. The [Fleet View](/features/fleet-view) Stack drill-down (a separate view, opened from a node card's **Stack details** button) does render colored **fleet label dots** next to each stack it lists.
Each label group header also carries a small kebab button for muting that label's notifications; see [Muting a label's notifications](#muting-a-labels-notifications) below.
### Fleet View tags filter
The [Fleet View](/features/fleet-view) overview toolbar carries a **Filters** popover whose sections include a **Tags** multi-select alongside the node-level filters. The Tags dropdown lists every label that exists on any node in the fleet, with each entry rendered as a colored dot plus the label name. Selecting one or more tags filters the node cards to nodes that contain at least one stack with that label.
A label that exists on only one of four nodes still appears in the dropdown; selecting it resolves to that single node.
## Working with labels
### Manage labels from Settings
**Settings · Organization · Labels** is the canonical place to create, rename, recolor, and delete labels. The masthead shows a `LABELS N/50` counter so you can see how close the active node is to the cap, and a per-row stack count tells you how many stacks currently carry each label.
The Labels panel requires the `labels` capability on the active node. If the active node does not advertise this capability, a lock card appears instead of the label list. Switching to a node that supports labels, or updating the node, resolves this.
Hover any row to reveal a **Pencil** edit icon, a destructive **Trash** icon, and (for admins whose node supports label muting) a **bell-off** icon that jumps straight to a prefilled mute rule for that label. The edit dialog shares its chrome with the create dialog: the kicker reads `LABELS · NEW` for a new label or `LABELS · EDIT` when you opened it from the pencil, the body has a single `Label name` input plus the ten color swatches, and the footer has **Cancel** and **Create** (or **Save**) buttons.
Deleting a label opens a destructive confirmation with the kicker `LABELS · DELETE · IRREVERSIBLE` and the body line `Removes the label from every stack across the fleet.` There is no undo: the label row is dropped, every assignment row pointing to it is dropped, and the affected stacks fall back to whatever other labels they still carry. Stacks left with no remaining labels move into the `UNLABELED` group on the next sidebar refresh.
### Create and assign inline from the stack menu
Right-clicking a stack in the sidebar (or using the three-dot kebab menu on its row) opens the same context menu under the **organize** group. Click **Labels** to open a submenu listing every label that exists on the active node, with a checkmark next to each one currently assigned to this stack. Clicking a label toggles the assignment immediately. Below a separator, two more items handle creation and full management, and a **Mute label…** entry (see below) can appear below a second separator:
- **New label** drops an inline form into the same submenu (text input with placeholder `Label name`, the ten color swatches, **Create** / **Cancel** buttons). Submitting creates the label on this node and assigns it to the stack in a single round trip. The entry hides itself once the node hits 50 labels.
- **Manage labels...** sends you to **Settings · Organization · Labels** for bulk renames, recolors, and deletions.
The **Labels** entry itself only appears in the context menu for users with edit rights on that stack (**admin** or **node-admin**); a viewer or deployer won't see it, even though they can still see label grouping and dots elsewhere. A stack can carry multiple labels and will then appear under each label's group in the sidebar. There is no per-stack label cap; the only cap is the per-node total of 50.
## Muting a label's notifications
Every Labels surface gives admins a shortcut into [Mute Rules](/features/alerts-notifications#mute-rules) scoped to a label, so a noisy group of stacks can be quieted without hand-building a rule. This requires the **admin** role and the active node advertising the `notification-suppression` capability; the mute controls simply don't render otherwise.
Two patterns are used, both wired to the same underlying rule fields (label, and an **Apply to** target of Bell / External / Both):
- **Instant presets**, available from the sidebar's per-label group-header kebab and from the stack context menu's **Mute label…** submenu (pick a label, then a preset): **Mute notifications for this label** (mutes bell and external delivery), **Mute external alerts for this label** (external channels only, bell stays active), and **Mute low-priority stack alerts** (mutes `info` and `warning` severities for the label, leaving `error` alerts audible). Each fires immediately and confirms with a toast; no dialog to review.
- **Prefilled review**, available from **Manage label mute rules** (the same two menus) and from the bell-off icon on each row in **Settings · Organization · Labels**. Both open **Settings · Notifications · Mute Rules** with a **New mute rule** dialog already filled in for that label (name `Mute label: `, the label pre-selected, **Both** as the target) so you can adjust node scope, categories, or severity before saving.
None of these delete or hide the underlying alerts; they only affect delivery to the bell, external channels, or both. See [Alerts & Notifications](/features/alerts-notifications#mute-rules) for the full Mute Rules field reference, suppression-vs-routing behavior, and how suppressed alerts still show up (marked **Suppressed**) in stack activity history.
## Fleet · Fleet Actions
The label-based Fleet Actions require the admin role. All other roles can view the cards but cannot execute them.
Two cards in the **Fleet · Actions** tab use labels to drive cross-node operations. See [Fleet Actions](/features/fleet-actions) for the full reference.
### Stop fleet by label
Type a stack label name into the input field. Sencho fans the request out to every node and stops every stack on that node assigned a stack label with the same name.
**Live preview.** As you type (debounced 500 ms), a suggestion listing the label's name, stack count, and node breakdown appears below the input, and a preview panel lists which stacks on which nodes would be stopped. The **Stop fleet** button stays disabled until the preview resolves to at least one matching stack.
**Dry run.** Click **Dry run** to simulate the operation without stopping any containers. The card shows the per-node breakdown labelled as a dry run and records the resolved target list. A completed dry run also unblocks the **Stop fleet** button when the live preview endpoint is unavailable.
This action targets stack labels only, never node labels. A confirmation modal shows the concrete list of nodes and stacks before the stop runs, and the stop is bound to that exact confirmed list; nothing added to the label between confirming and executing gets swept in. A node with no matching label is noted as such; an unreachable node is reported but never blocks the stop on reachable nodes.
### Bulk label assign
Pick a label that exists anywhere in the fleet, then tick the stacks you want across one or more nodes (grouped by node, with a filter and per-node select-all). **Reset** clears the current label pick and stack selection; **Apply** stays disabled until at least one target stack is checked.
When the chosen label name exists with different colors on different nodes, the card shows a notice: "This label uses different colors on different nodes. The shown color is applied where it is created." Color resolution order is: the local node's color first, then the most common color across nodes, then the first seen.
**Apply** adds the label to each chosen stack on its node, creating it there first with the chosen name and color if the node does not have it yet. Existing labels on the selected stacks are preserved. The confirmation modal summarizes the blast radius before you commit, and the result list breaks down per node, noting whether the label was created or reused.
## Limits and rules
- **50 labels per node.** Settings hides the **New label** button at the cap; the inline `New label` entry in the stack menu hides itself too.
- **Names are unique per node**, case-sensitive. The same name on two nodes is two separate label rows. Cross-node fleet stop and bulk assign both match by name across nodes; each node resolves the name to its own label (and bulk assign creates it there if missing).
- **Allowed name characters**: letters, digits, spaces, and hyphens. Empty names and names beyond 30 characters are rejected at the API.
- **Bulk-action concurrency**: only one label-driven bulk action can run on a single node at a time. A second concurrent attempt against the same node returns HTTP 429 and the operator sees an error toast; the in-flight action keeps running.
- **Bulk assign size cap**: a single Apply is capped at 1,000 total stack assignments across every selected node; the request is rejected past that so one accidental fleet-wide selection can't force an unbounded number of writes.
- **Permissions**: every signed-in user can view labels: sidebar grouping, the Settings panel (read-only), and the Fleet View Tags filter all work for every user. Creating, renaming, recoloring, deleting labels, and toggling a label's assignment on a stack (including from the context menu) requires the **admin** or **node-admin** role. The label-based Fleet Actions (Stop fleet by label, Bulk label assign) and the mute shortcuts require the **admin** role.
Beyond the UI, an admin can drive one label at a time on the current node through the API: `POST /api/labels/:id/action` with `{ "action": "deploy" | "stop" | "restart", "dryRun": true }` runs that action across every stack carrying the label, node-locked against other bulk operations the same way the fleet cards are. There's no button for this yet, so it's reachable only via a **Full Admin** API token or a direct request from an admin session; see [API Tokens](/features/api-tokens) for how to mint one.
## Troubleshooting
Grouping requires at least one stack to carry at least one label. With zero labels assigned the sidebar collapses into a single `UNLABELED` group, which is rendered as a flat list. Create a label from **Settings · Organization · Labels** or right-click any stack and use **Labels · New label**, assign it to a stack, and the grouped layout takes over.
The **Labels** submenu (both viewing checkmarks and toggling assignment) requires **admin** or **node-admin** rights on that stack. Viewers and deployers can still see the sidebar grouping and the read-only Settings panel, but the context menu won't offer a way to change labels.
The active node already has 50 labels (the per-node cap). Both the inline New label entry in the stack submenu and the New label button in **Settings · Organization · Labels** hide themselves at the cap. Delete an unused label or rename an existing one to free a slot.
The Tags filter aggregates labels across every node in the fleet by name. If the new label only exists on one node and that node was offline at the moment the page loaded, the dropdown may not include it. Refresh **Fleet · Overview** with the toolbar refresh button to repull node state.
The active node does not advertise the `labels` capability. Switch to a node that supports labels, or update the node to a version that includes this capability.
Stack labels are per-node, so the fleet-stop matches by name across nodes. If the stack label you typed only exists on one node and you typed the wrong case (`prod` versus `Prod`), no node will match. The picker queries each reachable node for its own stack labels; node labels never appear there. A label on a node Sencho cannot currently reach will not be suggested, and the picker flags that the list may be incomplete. Pick from the suggestion list rather than typing freehand to avoid case mistakes.
By design it never does: the card only adds the label you picked, leaving each stack's other labels intact. There is no clear or replace mode. To remove or swap a stack's labels, edit them from that stack's own **Labels** menu.
Confirm the node was reachable when you applied: an unreachable node is shown in the target list and reported in the per-node results rather than silently skipped. If the node was reachable, the label is created there by name with the chosen color and assigned; re-run to retry any node that failed.
The label-based Fleet Actions require the admin role. Confirm the active user has the admin role under **Settings · Users**; all other roles see the cards but cannot execute them.
Label muting requires the **admin** role and the active node advertising the `notification-suppression` capability. Update the node if it's on an older version, or confirm your role under **Settings · Users**.
Working as designed. The destructive confirmation reads `Removes the label from every stack across the fleet.` The label row and every assignment row that pointed to it are dropped in a single transaction. There is no undo; recreate the label by name and color and reassign the affected stacks if you need to recover.
## Related features
See fleet label dots per stack in the drill-down, and filter the whole fleet by tag.
The full reference for every cross-node action, including Stop by label and Bulk label assign.
The complete Mute Rules field reference and how suppression interacts with routing.
Audit Compose-level and Node labels, the two label systems Stack Labels is deliberately kept separate from.