# Validator and RPC Node Deployment Strategy

## Core Requirements

### Validator Nodes
- **Deployment**: ALL non-US Commercial Azure regions (42 regions)
- **VM Size**: `Standard_D4_v2` (4 vCPUs) - **MUST be the SAME across ALL regions**
- **VM Family**: Dv2 Family
- **Count**: 1 validator per region (minimum for consensus)
- **Purpose**: Consensus and block validation
- **Critical**: All validator nodes must use identical VM specifications

### RPC Nodes (Core Backbone)
- **Deployment**: ALL non-US Commercial Azure regions (42 regions)
- **VM Size**: `Standard_D8s_v6` (8 vCPUs) - **MUST be the SAME across ALL regions**
- **VM Family**: Dsv6 Family
- **Count**: 1 RPC node per region (core backbone)
- **Purpose**: Internal networking, core backbone infrastructure
- **Critical**: RPC nodes are the internally networked backbone - must be in ALL regions

### System Nodes
- **Deployment**: ALL regions (required for AKS)
- **VM Size**: `Standard_D2_v2` (2 vCPUs)
- **VM Family**: Dv2 Family
- **Count**: 1 system node per region
- **Purpose**: AKS system pool

### Sentry Nodes
- **Deployment**: Distributed as needed based on quotas
- **VM Size**: `Standard_D4_v2` (4 vCPUs)
- **VM Family**: Dv2 Family
- **Count**: 0-1 per region (distributed)
- **Purpose**: P2P connectivity
- **Note**: Can be distributed based on quota availability

## All 42 Non-US Commercial Azure Regions

| # | Region | Code | Validator | RPC | System | Sentry |
|---|--------|------|-----------|-----|--------|--------|
| 1 | Belgium Central | bc | ✅ | ✅ | ✅ | ⚪ |
| 2 | Brazil South | bs | ✅ | ✅ | ✅ | ⚪ |
| 3 | Brazil Southeast | bse | ✅ | ✅ | ✅ | ⚪ |
| 4 | Canada Central | cc | ✅ | ✅ | ✅ | ⚪ |
| 5 | Canada East | ce | ✅ | ✅ | ✅ | ⚪ |
| 6 | Central India | ci | ✅ | ✅ | ✅ | ⚪ |
| 7 | Chile Central | chc | ✅ | ✅ | ✅ | ⚪ |
| 8 | East Asia | ea | ✅ | ✅ | ✅ | ⚪ |
| 9 | France Central | fc | ✅ | ✅ | ✅ | ⚪ |
| 10 | France South | fs | ✅ | ✅ | ✅ | ⚪ |
| 11 | Germany North | gn | ✅ | ✅ | ✅ | ⚪ |
| 12 | Germany West Central | gwc | ✅ | ✅ | ✅ | ⚪ |
| 13 | Indonesia Central | ic | ✅ | ✅ | ✅ | ⚪ |
| 14 | Israel Central | ilc | ✅ | ✅ | ✅ | ⚪ |
| 15 | Italy North | in | ✅ | ✅ | ✅ | ⚪ |
| 16 | Japan East | je | ✅ | ✅ | ✅ | ⚪ |
| 17 | Japan West | jw | ✅ | ✅ | ✅ | ⚪ |
| 18 | Jio India Central | jic | ✅ | ✅ | ✅ | ⚪ |
| 19 | Jio India West | jiw | ✅ | ✅ | ✅ | ⚪ |
| 20 | Korea Central | kc | ✅ | ✅ | ✅ | ⚪ |
| 21 | Korea South | ks | ✅ | ✅ | ✅ | ⚪ |
| 22 | Malaysia West | mw | ✅ | ✅ | ✅ | ⚪ |
| 23 | Mexico Central | mc | ✅ | ✅ | ✅ | ⚪ |
| 24 | New Zealand North | nzn | ✅ | ✅ | ✅ | ⚪ |
| 25 | North Europe | ne | ✅ | ✅ | ✅ | ⚪ |
| 26 | Norway East | no | ✅ | ✅ | ✅ | ⚪ |
| 27 | Norway West | nw | ✅ | ✅ | ✅ | ⚪ |
| 28 | Poland Central | pc | ✅ | ✅ | ✅ | ⚪ |
| 29 | Qatar Central | qc | ✅ | ✅ | ✅ | ⚪ |
| 30 | South Africa North | san | ✅ | ✅ | ✅ | ⚪ |
| 31 | South Africa West | saw | ✅ | ✅ | ✅ | ⚪ |
| 32 | Southeast Asia | sea | ✅ | ✅ | ✅ | ⚪ |
| 33 | South India | si | ✅ | ✅ | ✅ | ⚪ |
| 34 | Spain Central | sc | ✅ | ✅ | ✅ | ⚪ |
| 35 | Sweden Central | swc | ✅ | ✅ | ✅ | ⚪ |
| 36 | Switzerland North | sn | ✅ | ✅ | ✅ | ⚪ |
| 37 | Switzerland West | sw | ✅ | ✅ | ✅ | ⚪ |
| 38 | UAE Central | uac | ✅ | ✅ | ✅ | ⚪ |
| 39 | UAE North | uan | ✅ | ✅ | ✅ | ⚪ |
| 40 | UK South | uks | ✅ | ✅ | ✅ | ⚪ |
| 41 | UK West | ukw | ✅ | ✅ | ✅ | ⚪ |
| 42 | West Europe | we | ✅ | ✅ | ✅ | ⚪ |
| 43 | West India | wi | ✅ | ✅ | ✅ | ⚪ |

**Legend**: ✅ = Required, ⚪ = Optional (distributed)

## Per-Region Configuration

### Standard Configuration

```hcl
node_count = {
  system     = 1  # Required for AKS
  validators = 1  # Required in ALL regions (SAME VM size)
  sentries   = 0  # Optional, distributed as needed
  rpc        = 1  # Required in ALL regions (core backbone)
}

vm_families = {
  system     = "Standard_D2_v2"       # 2 vCPUs - Dv2 Family
  validators = "Standard_D4_v2"       # 4 vCPUs - Dv2 Family (SAME across ALL)
  sentries   = "Standard_D4_v2"        # 4 vCPUs - Dv2 Family (distributed)
  rpc        = "Standard_D8s_v6"      # 8 vCPUs - Dsv6 Family (SAME across ALL)
}
```

### Quota Requirements Per Region

- **Dv2 Family**: 6 vCPUs (system: 2, validators: 4, sentries: 0)
- **Dsv6 Family**: 8 vCPUs (RPC: 8)
- **Total**: 14 vCPUs per region (minimum)

With sentries:
- **Dv2 Family**: 10 vCPUs (system: 2, validators: 4, sentries: 4)
- **Dsv6 Family**: 8 vCPUs (RPC: 8)
- **Total**: 18 vCPUs per region (with sentries)

## Total Deployment Summary

### Global Resources

- **Total Regions**: 42 (all non-US Commercial Azure)
- **Total Validator Nodes**: 42 (1 per region, SAME VM size)
- **Total RPC Nodes**: 42 (1 per region, core backbone)
- **Total System Nodes**: 42 (1 per region, AKS)
- **Total Sentry Nodes**: 0-42 (distributed as needed)
- **Total Nodes**: 126-168 nodes

### Total vCPUs

**Minimum (without sentries)**:
- **Dv2 Family**: 252 vCPUs (6 per region × 42)
- **Dsv6 Family**: 336 vCPUs (8 per region × 42)
- **Total**: 588 vCPUs

**Maximum (with sentries)**:
- **Dv2 Family**: 420 vCPUs (10 per region × 42)
- **Dsv6 Family**: 336 vCPUs (8 per region × 42)
- **Total**: 756 vCPUs

## Key Design Principles

### 1. Validator Consistency
- **Same VM size** (`Standard_D4_v2`) across ALL 42 regions
- Ensures consistent performance and behavior
- Simplifies monitoring and management
- Critical for consensus reliability

### 2. RPC Backbone
- **RPC nodes in ALL 42 regions** for core backbone
- Internally networked for high availability
- Critical infrastructure component
- Same VM size (`Standard_D8s_v6`) across all regions

### 3. Flexible Distribution
- **System nodes**: Required in all regions (AKS)
- **Sentry nodes**: Distributed based on quotas and needs
- Allows optimization per region

## Deployment Configuration

The configuration is defined in `terraform/multi-region-global.tf`:

- Uses `local.standard_validator_vm_size = "Standard_D4_v2"` for all validators
- Uses `local.standard_rpc_vm_size = "Standard_D8s_v6"` for all RPC nodes
- Automatically generates configuration for all 42 regions
- Ensures consistency across all regions

## Monitoring

### Validator Monitoring
- Monitor all 42 validator nodes
- Ensure all use `Standard_D4_v2`
- Track consensus health across regions
- Alert on any validator VM size deviations

### RPC Backbone Monitoring
- Monitor all 42 RPC nodes
- Ensure all use `Standard_D8s_v6`
- Track internal networking health
- Monitor cross-region connectivity

## Benefits

1. **Consistent Validators**: Same VM size ensures uniform behavior
2. **Resilient Backbone**: RPC nodes in all regions for redundancy
3. **Global Coverage**: 42 regions provide worldwide presence
4. **Flexible Scaling**: System/sentry nodes can be adjusted per region
5. **High Availability**: Geographic redundancy across all regions

