docs: rework naming conventions with structured hostname format (Phase 0 - #31)

Format: <SITE>-<ZONE>-<ROLE>-<ID> (e.g., PA-DC-LEAF-01)
- Site prefix registry (2 chars: PA, LY, MA...)
- Zone codes: DC, DR, LAB, CO
- Interface descriptions reference full hostnames
- MLAG domain-id now unique per pair
- IPAM identifiers aligned with new naming
- BGP session descriptions standardized

docs/fabric-standardization.md

@@ -36,11 +36,11 @@ Spines use a simple sequential mapping: one Ethernet port per leaf.
 
 | Port | Role | Connected to |
 |------|------|-------------|
-| Ethernet1 | Underlay downlink | leaf1 |
+| Ethernet1 | Underlay downlink | Leaf 01 |
-| Ethernet2 | Underlay downlink | leaf2 |
+| Ethernet2 | Underlay downlink | Leaf 02 |
-| Ethernet3 | Underlay downlink | leaf3 |
+| Ethernet3 | Underlay downlink | Leaf 03 |
 | ... | ... | ... |
-| Ethernet{N} | Underlay downlink | leaf{N} |
+| Ethernet{N} | Underlay downlink | Leaf {N} |
 
 All spine downlinks are:
 - **Routed** (`no switchport`)
@@ -62,7 +62,7 @@ Leaf port allocation follows a fixed layout. Ports are divided into 3 zones:
 
 ### 3.1 Host-facing ports (Ethernet1-9)
 - Each physical port is a member of a Port-Channel
-- Port-Channel number = MLAG ID = host index (e.g., host1 → Po1, MLAG 1)
+- Port-Channel number = MLAG ID = host index (e.g., host 01 → Po1, MLAG 1)
 - Mode: `switchport mode trunk`
 - VLANs: only the VLANs needed by the host
 - LACP fallback enabled (timeout 5, individual)
@@ -74,47 +74,133 @@ Leaf port allocation follows a fixed layout. Ports are divided into 3 zones:
 - Carries MLAG control traffic + VLANs 4090, 4091
 
 ### 3.3 Spine uplinks (Ethernet11-12)
-- Ethernet11 → spine1, Ethernet12 → spine2
+- Ethernet11 → spine 01, Ethernet12 → spine 02
 - Fixed mapping, never changes regardless of fabric size
 
 ---
 
 ## 4. Naming conventions
 
-### 4.1 Devices
+### 4.1 Device hostname format
 
-| Role | Pattern | Examples |
+All device hostnames follow the pattern:
-|------|---------|---------|
-| Spine | `spine{N}` | spine1, spine2 |
-| Leaf | `leaf{N}` | leaf1, leaf2, ..., leaf8 |
-| Host | `host{N}` | host1, host2, host3, host4 |
 
-- Leafs are numbered sequentially: odd = primary, even = secondary within a pair
+```
-  - Pair 1: leaf1 (primary), leaf2 (secondary)
+<SITE>-<ZONE>-<ROLE>-<ID>
-  - Pair 2: leaf3 (primary), leaf4 (secondary)
+```
-  - Pair N: leaf{2N-1} (primary), leaf{2N} (secondary)
 
-### 4.2 MLAG domain
+| Field | Length | Description | Values |
-- Domain ID: `leafs` (same for all pairs — Arista uses this as an identifier within the MLAG)
+|-------|--------|-------------|--------|
-- Peer-link: Port-Channel999
+| `SITE` | 2 chars | City / location code (uppercase) | PA (Paris), LY (Lyon), MA (Marseille), LO (London)... |
-- Peer-link VLAN: 4090
+| `ZONE` | 2-3 chars | Network area (uppercase) | DC (Datacenter), DR (Disaster Recovery), LAB (Lab), CO (Colocation) |
-- iBGP peering VLAN: 4091
+| `ROLE` | 4-5 chars | Device function (uppercase) | SPINE, LEAF, HOST |
+| `ID` | 2 digits | Sequential number (zero-padded) | 01, 02, ..., 99 |
 
-### 4.3 Fabric
+**Examples for Paris datacenter:**
-- Pattern: `{site}-{function}` (e.g., `dc1-evpn`, `paris-evpn`)
 
-### 4.4 IPAM identifiers (for resource pool idempotence)
+| Device | Hostname |
+|--------|----------|
+| Spine 1 | `PA-DC-SPINE-01` |
+| Spine 2 | `PA-DC-SPINE-02` |
+| Leaf 1 (pair 1, primary) | `PA-DC-LEAF-01` |
+| Leaf 2 (pair 1, secondary) | `PA-DC-LEAF-02` |
+| Leaf 3 (pair 2, primary) | `PA-DC-LEAF-03` |
+| Leaf 4 (pair 2, secondary) | `PA-DC-LEAF-04` |
+| Host 1 | `PA-DC-HOST-01` |
+
+**Examples for Lyon disaster recovery:**
+
+| Device | Hostname |
+|--------|----------|
+| Spine 1 | `LY-DR-SPINE-01` |
+| Leaf 1 | `LY-DR-LEAF-01` |
+
+### 4.2 Leaf pairing rule
+
+Leafs are numbered sequentially. **Odd = primary, even = secondary** within a pair:
+
+| Pair | Primary | Secondary | VTEP |
+|------|---------|-----------|------|
+| 1 | `{SITE}-{ZONE}-LEAF-01` | `{SITE}-{ZONE}-LEAF-02` | VTEP 1 |
+| 2 | `{SITE}-{ZONE}-LEAF-03` | `{SITE}-{ZONE}-LEAF-04` | VTEP 2 |
+| 3 | `{SITE}-{ZONE}-LEAF-05` | `{SITE}-{ZONE}-LEAF-06` | VTEP 3 |
+| 4 | `{SITE}-{ZONE}-LEAF-07` | `{SITE}-{ZONE}-LEAF-08` | VTEP 4 |
+
+### 4.3 Fabric name
+
+The fabric is identified by `{SITE}-{ZONE}` (lowercase in Infrahub objects):
+
+| Infrahub object | Name | Example |
+|----------------|------|---------|
+| `InfraFabric` | `{site}-{zone}` | `pa-dc` |
+| `LocationSite` | `{site}-{zone}` | `pa-dc` |
+
+### 4.4 Interface descriptions
+
+Interface descriptions reference the **full hostname** of the remote device:
+
+| Interface | Description format | Example (on PA-DC-LEAF-01) |
+|-----------|-------------------|----------------------------|
+| Spine uplink Eth11 | `to {REMOTE_HOSTNAME}` | `to PA-DC-SPINE-01` |
+| Spine uplink Eth12 | `to {REMOTE_HOSTNAME}` | `to PA-DC-SPINE-02` |
+| MLAG peer-link Eth10 | `mlag peer link` | `mlag peer link` |
+| Host-facing Eth1 | `to {HOST_HOSTNAME}` | `to PA-DC-HOST-01` |
+| Loopback0 | `Router-ID` | `Router-ID` |
+| Loopback1 | `VTEP` | `VTEP` |
+
+On spines:
+
+| Interface | Description format | Example (on PA-DC-SPINE-01) |
+|-----------|-------------------|----------------------------|
+| Downlink Eth1 | `to {REMOTE_HOSTNAME}` | `to PA-DC-LEAF-01` |
+| Loopback0 | `Router-ID` | `Router-ID` |
+
+### 4.5 MLAG domain
+
+| Parameter | Value | Notes |
+|-----------|-------|-------|
+| Domain ID | `{site}-{zone}-pair{NN}` | e.g., `pa-dc-pair01` — unique per MLAG pair |
+| Peer-link | Port-Channel999 | Fixed |
+| Peer-link VLAN | 4090 | Fixed |
+| iBGP peering VLAN | 4091 | Fixed |
+
+### 4.6 BGP descriptions
+
+| Session type | Description format | Example |
+|-------------|-------------------|---------|
+| eBGP underlay | `underlay to {REMOTE_HOSTNAME}` | `underlay to PA-DC-SPINE-01` |
+| iBGP MLAG peer | `ibgp to {REMOTE_HOSTNAME}` | `ibgp to PA-DC-LEAF-02` |
+| EVPN overlay | `evpn to {REMOTE_HOSTNAME}` | `evpn to PA-DC-SPINE-01` |
+
+### 4.7 IPAM identifiers (for resource pool idempotence)
+
+All identifiers use **lowercase**, with the fabric name `{site}-{zone}`:
 
 | Object | Identifier pattern | Example |
 |--------|-------------------|---------|
-| Site infra prefix | `site-{site}-infra` | `site-dc1-infra` |
+| Site infra prefix | `site-{site}-{zone}-infra` | `site-pa-dc-infra` |
-| Site services prefix | `site-{site}-services` | `site-dc1-services` |
+| Site services prefix | `site-{site}-{zone}-services` | `site-pa-dc-services` |
-| Device loopback0 IP | `lo0-{fabric}-{device}` | `lo0-evpnlab-leaf1` |
+| Device loopback0 IP | `lo0-{site}-{zone}-{role}-{id}` | `lo0-pa-dc-leaf-01` |
-| Device loopback1 IP | `lo1-{fabric}-vtep{pair}` | `lo1-evpnlab-vtep1` |
+| Device loopback1 IP | `lo1-{site}-{zone}-vtep{NN}` | `lo1-pa-dc-vtep01` |
-| Underlay P2P /31 | `p2p-{fabric}-{spine}-{leaf}` | `p2p-evpnlab-spine1-leaf1` |
+| Underlay P2P /31 | `p2p-{site}-{zone}-spine{NN}-leaf{NN}` | `p2p-pa-dc-spine01-leaf01` |
-| MLAG peer /31 | `mlag-peer-{fabric}-pair{N}` | `mlag-peer-evpnlab-pair1` |
+| MLAG peer /31 | `mlag-peer-{site}-{zone}-pair{NN}` | `mlag-peer-pa-dc-pair01` |
-| MLAG iBGP /31 | `mlag-ibgp-{fabric}-pair{N}` | `mlag-ibgp-evpnlab-pair1` |
+| MLAG iBGP /31 | `mlag-ibgp-{site}-{zone}-pair{NN}` | `mlag-ibgp-pa-dc-pair01` |
-| Leaf ASN | `asn-{fabric}-pair{N}` | `asn-evpnlab-pair1` |
+| Leaf ASN | `asn-{site}-{zone}-pair{NN}` | `asn-pa-dc-pair01` |
+
+### 4.8 Site prefix registry
+
+To avoid conflicts, site prefixes must be registered:
+
+| Prefix | City | Country |
+|--------|------|---------|
+| PA | Paris | FR |
+| LY | Lyon | FR |
+| MA | Marseille | FR |
+| LO | London | UK |
+| FR | Frankfurt | DE |
+| AM | Amsterdam | NL |
+
+> This registry is maintained as a reference. The `SITE` code is stored on the `LocationSite` object in Infrahub.
 
 ---
 
@@ -169,7 +255,7 @@ Each site receives:
 ### 6.2 Leaf ASN
 - **One ASN per MLAG pair** (iBGP within pair, eBGP to spines)
 - Allocated from a `CoreNumberPool` (range: 65001–65099)
-- Deterministic via identifier: `asn-{fabric}-pair{N}`
+- Deterministic via identifier: `asn-{site}-{zone}-pair{NN}`
 
 ### 6.3 BGP configuration standards
 
@@ -215,7 +301,7 @@ Spine underlay neighbors are configured individually (no peer-group) since each
 
 | Parameter | Value |
 |-----------|-------|
-| Domain ID | `leafs` |
+| Domain ID | `{site}-{zone}-pair{NN}` (e.g., `pa-dc-pair01`) |
 | Peer-link interface | Port-Channel999 |
 | Peer-link VLAN | 4090 (IP: /31 from MLAG peer pool) |
 | iBGP VLAN | 4091 (IP: /31 from MLAG iBGP pool, MTU 9214) |
@@ -225,8 +311,8 @@ Spine underlay neighbors are configured individually (no peer-group) since each
 | Virtual MAC | `c001.cafe.babe` (fabric-wide anycast gateway) |
 
 ### 7.1 Primary/secondary assignment
-- **Odd-numbered leaf** (leaf1, leaf3, leaf5, leaf7): lower IP on MLAG VLANs (e.g., x.x.x.254/31)
+- **Odd-numbered leaf** (LEAF-01, LEAF-03, LEAF-05, LEAF-07): lower IP on MLAG VLANs (e.g., x.x.x.0/31)
-- **Even-numbered leaf** (leaf2, leaf4, leaf6, leaf8): higher IP (e.g., x.x.x.255/31)
+- **Even-numbered leaf** (LEAF-02, LEAF-04, LEAF-06, LEAF-08): higher IP (e.g., x.x.x.1/31)
 
 ---