Target Assignment

Assign targets to environments to enable deployments.

Why Assign Targets?

Targets must be assigned to environments to:

• Receive deployments for that environment
• Be included in environment-based target selection
• Participate in the promotion pipeline

Assignment Properties

Each target-environment assignment includes:

Property	Description
Target	The machine being assigned
Environment	The destination environment
Priority	Deployment order within environment

Priority Explained

Priority determines deployment order. Values range from -100 to 100 and default to 50. Higher priority values deploy first:

Priority	Meaning
100	First to deploy
80	Earlier
50	Default
10	Later
-100	Last

Tip

Use higher priorities for canary targets that should deploy first.

Assigning Targets

From Environment Detail

┌─────────────────────────────────────────────────────────────┐
│  Production - Targets                                       │
├─────────────────────────────────────────────────────────────┤
│                                                             │
│  Assigned Targets (12):                                     │
│  ┌────────────────┬──────────┬──────────┬────────────────┐ │
│  │ Target         │ Status   │ Priority │ Actions        │ │
│  ├────────────────┼──────────┼──────────┼────────────────┤ │
│  │ web-prod-01    │ ● Online │ 1        │ [Remove]       │ │
│  │ web-prod-02    │ ● Online │ 2        │ [Remove]       │ │
│  │ web-prod-03    │ ● Online │ 3        │ [Remove]       │ │
│  │ db-prod-01     │ ● Online │ 10       │ [Remove]       │ │
│  └────────────────┴──────────┴──────────┴────────────────┘ │
│                                                             │
│  [+ Add Target]                                             │
│                                                             │
└─────────────────────────────────────────────────────────────┘

Click Add Target to assign:

┌─────────────────────────────────────────────────────────────┐
│  Add Target to Production                                   │
├─────────────────────────────────────────────────────────────┤
│                                                             │
│  Target:    [Select target...              ▼]               │
│             ├── web-prod-04 (Online)                        │
│             ├── web-prod-05 (Online)                        │
│             └── worker-01 (Stale)                           │
│                                                             │
│  Priority:  [50                             ]               │
│                                                             │
│  ┌───────────────────────────────────────────────────────┐  │
│  │ Higher priority numbers deploy first (range -100..100).│  │
│  │ Use 90+ for web servers, lower for databases.         │  │
│  └───────────────────────────────────────────────────────┘  │
│                                                             │
│                           [Cancel]  [Add]                   │
│                                                             │
└─────────────────────────────────────────────────────────────┘

Via REST API

Target-to-environment assignment is managed in Lens or via POST /api/v1/environments/{environment_id}/targets. Each call assigns one target with a priority (assignment is by target ID, not tag):

# Assign a single target with a priority
curl -X POST "$MANTIS_URL/api/v1/environments/<environment-id>/targets" \
  -H "Authorization: Bearer $TOKEN" -H "Content-Type: application/json" \
  -d '{"target_id": "<web-prod-04-id>", "priority": 4}'

# Assign multiple targets by repeating the call
for id in <id-4> <id-5> <id-6>; do
  curl -X POST "$MANTIS_URL/api/v1/environments/<environment-id>/targets" \
    -H "Authorization: Bearer $TOKEN" -H "Content-Type: application/json" \
    -d "{\"target_id\": \"$id\", \"priority\": 5}"
done

Editing Assignments

Change Priority via API

Update priorities for multiple targets:

# Update a target's priority within an environment (PATCH by target ID)
curl -X PATCH "$MANTIS_URL/api/v1/environments/<environment-id>/targets/<target-id>" \
  -H "Authorization: Bearer $TOKEN" -H "Content-Type: application/json" \
  -d '{"priority": 1}'

Removing Assignments

Single Removal

1. Navigate to the environment’s Targets page
2. Click Remove next to the target
3. Confirm removal

┌─────────────────────────────────────────────────────────────┐
│  Remove from Environment                                    │
├─────────────────────────────────────────────────────────────┤
│                                                             │
│  Remove web-prod-01 from Production?                        │
│                                                             │
│  The target will no longer receive deployments              │
│  for this environment.                                      │
│                                                             │
│                           [Cancel]  [Remove]                │
│                                                             │
└─────────────────────────────────────────────────────────────┘

Bulk Removal

# Remove targets one at a time (DELETE by target ID)
for id in <web-prod-04-id> <web-prod-05-id>; do
  curl -X DELETE "$MANTIS_URL/api/v1/environments/<environment-id>/targets/$id" \
    -H "Authorization: Bearer $TOKEN"
done

Multiple Environment Assignments

A target can belong to multiple environments. For example, shared-cache-01 can be assigned to both Staging and Production with independent priority values per environment. Each environment’s Targets page lists the target separately with its own Remove action.

Caution

Targets in multiple environments may receive conflicting deployments. Use with caution.

Assignment Strategies

By Server Role

Production Environment:
├── web-prod-01 (priority: 100) - Canary
├── web-prod-02 (priority: 90) - Web tier
├── web-prod-03 (priority: 90) - Web tier
├── api-prod-01 (priority: 80) - API tier
├── api-prod-02 (priority: 80) - API tier
└── db-prod-01 (priority: 10) - Database

By Geographic Region

Production Environment:
├── us-east-web-01 (priority: 100)
├── us-east-web-02 (priority: 100)
├── us-west-web-01 (priority: 90)
├── us-west-web-02 (priority: 90)
├── eu-west-web-01 (priority: 80)
└── eu-west-web-02 (priority: 80)

Canary + Fleet

Production Environment:
├── web-canary-01 (priority: 100)  ← Deploys first
├── web-prod-01 (priority: 50)
├── web-prod-02 (priority: 50)
├── web-prod-03 (priority: 50)
└── web-prod-04 (priority: 50)

Deployment Order

Priority determines order within execution modes (higher priority first):

Sequential Mode

Priority 100: web-canary-01 (first)
Priority 90: web-prod-01 (second)
Priority 90: web-prod-02 (second, after web-prod-01)
Priority 10: db-prod-01 (last)

Rolling Mode

Targets are ordered by priority, then split into batches of batch_size — batch boundaries come from the count, not the priority value. With batch_size = 2:

Order (by priority): web-canary-01 (100), web-prod-01 (90), web-prod-02 (90), db-prod-01 (10)

Batch 1: web-canary-01, web-prod-01
Batch 2: web-prod-02, db-prod-01

Parallel Mode

All targets in the same step start simultaneously. There is no priority-based ordering or completion tracking in parallel mode — every target in the step fires at once (target priority only affects the order in which targets are listed).

Best Practices

1. Plan Your Priority Scheme

Define a consistent priority scheme (higher deploys first, range -100..100):

Priority Range	Purpose
100	Canary/test targets
90-99	Web/API tier
70-89	Backend services
50-69	Worker nodes
<50	Databases, critical services

2. Use Tags for Organization

Combine tags with environments:

Target: web-prod-01
Tags:
  role: web
  tier: frontend
  region: us-east
Environment: Production (priority: 100)

3. Document Assignments

Maintain a record of assignments:

Target	Environment	Priority	Rationale
web-canary	Production	100	First to deploy, catch issues early
web-prod-*	Production	90	Main web tier
db-prod	Production	10	Deploy after app servers

4. Review Regularly

Periodically audit assignments:

• Remove decommissioned targets
• Update priorities as needed
• Verify new targets are assigned

Troubleshooting

Target Not Receiving Deployments

Cause: Target not assigned to environment

Solution: Add target to the environment

Wrong Deployment Order

Cause: Priority values incorrect

Solution: Review and update priority values

Target in Wrong Environment

Cause: Incorrect assignment

Solution: Remove from wrong environment, add to correct one

Duplicate Assignments

Cause: Target assigned twice to same environment

Solution: This shouldn’t be possible; check for data issues

Next Steps

• Creating Environments - Set up environments
• Environment State - Track deployed versions
• Promotions - Promote between environments
• Overview - Return to environments overview