Networking

Address Allocation Rules

Default role bands, stable physical-host octets, host-interface addressing policy, and documented exceptions for pinned services and VIPs.

Role bands make unassigned address space predictable, while a stable last octet identifies each physical host across the infrastructure VLANs it terminates. Exact entries in the IP Tables remain authoritative when a pinned service or VIP intentionally uses another band.

Default Bands

Last-octet rangeDefault use
.1OPNsense gateway on a routed subnet
.2-.9Network infrastructure such as switches and APs
.10-.39Physical host interfaces using the host-octet convention
.40-.49Infrastructure service VMs and appliances
.50-.199DHCP pools or additional static services
.200-.254VIPs, MetalLB pools, and load-balancer addresses

Bands Are Allocation Guardrails

The bands guide new assignments; they do not replace the exact address registry. Pinned DNS, Proxmox Backup Server, Kubernetes API, and ingress addresses already occupy documented exceptions. Check the IP tables before assigning an address.

Networks Without a Gateway

The .1 convention applies only where a routed subnet exists.

VLANSite scopeAddressing rule
25Both sitesCorosync peers receive direct addresses with no gateway
60Both sitesStorage consumers receive direct addresses with no gateway
65Site BCeph cluster peers receive direct addresses with no gateway
65Site APrefix reserved; VLAN not carried
999Site ANo IP subnet at all

Do Not Add a Convenience Gateway

VLANs 25 and 60 remain local-only. VLAN 65 remains isolated at Site B and reserved at Site A. Routing VLAN 60 to VLAN 65 or adding a default gateway is an architecture change, not a routine firewall adjustment.

Physical Host Octets

A physical host reuses the same last octet on each infrastructure VLAN where it holds an address. For example, sa-stor-01 uses .20 on Proxmox management, Corosync, storage, and backup networks.

HostSiteStable octet
sa-edge-01Site A10
sa-cmp-01Site A11
sa-cmp-02Site A12
sa-stor-01Site A20
sb-edge-01Site B10
sb-cmp-01Site B20
sb-cmp-02Site B21
sb-cmp-03Site B30
sb-cmp-04Site B31
sb-cmp-05Site B32

Host Interface Policy

Proxmox receives an L3 address only on infrastructure networks used by the host itself. Workload and client VLANs may cross a VLAN-aware bridge, but the bridge does not receive a host address on those segments.

Network groupProxmox host behavior
VLAN 10, Network Mgmt / IPMISwitches, APs, and BMCs receive addresses; the Proxmox host OS does not
VLAN 20, Proxmox ManagementEvery Proxmox node receives its primary management address
VLAN 25, Corosync heartbeatEvery cluster node receives its stable host octet with no gateway
VLAN 60, Storage / Ceph publicApproved storage and compute nodes receive direct addresses; edge nodes are excluded
VLAN 65, Ceph clusterSite B Ceph nodes only; Site A does not carry the VLAN
VLAN 90, Backup / ReplicationApproved storage and compute nodes receive addresses; edge nodes are excluded
VLANs 30, 40, 50, 70, 80, 100, 110, 120Bridged to workloads or clients with no Proxmox host address

/22 Allocation Exceptions

VLANs 40 and 100 span four /24 boundaries, so their exact allocations matter more than the shorthand band table.

NetworkExact rule
Kubernetes Nodes, VLAN 40Physical-node addresses use the first /24 and the stable host octet, such as 10.10.40.11
Lab / Trusted Client, VLAN 100 at Site ADHCP spans 10.10.100.50-10.10.103.199

Do not infer that an unused-looking address in a /22 is available. Confirm it against the IP Tables and VLANs and Routing. Use DHCP and IPAM Operations for the allocation, reservation, and reconciliation workflow.