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Create an OVN Logical Switch

OVN logical switches are MFCloud's tenant networks — VMs and containers attached to the same switch share an L2 broadcast domain regardless of which compute node they land on.

Quick steps

  1. Networks → OVN → + New Logical Switch.
  2. Fill in:
  3. Name — short, lowercase, no spaces (e.g. prod-web).
  4. Subnet (optional) — CIDR for the IPAM pool that gets auto-created (e.g. 10.50.10.0/24).
  5. Gateway (optional) — first usable IP if you want OVN to act as default GW.
  6. DNS Server (optional) — handed out via DHCP to attached endpoints.
  7. Tenant (admin only) — limits visibility of the switch to one tenant.
  8. Create.

The switch is created in OVN's northbound database (ls-add prod-web) immediately. Logical-switch ports (lsp-*) attach when you bind a VM or container to it.

Subnet + IPAM in one shot

If you supplied a Subnet at create time MFCloud also creates an IPAM pool named after the switch, with range_start = first usable IP, range_end = last usable IP, and gateway = your input. From then on every VM/container created with pool_id=<this> gets an IP allocated, and an OVN LSP added automatically.

Inspecting a switch

# On any OVN-enabled host
ovn-nbctl show               # tree of switches, ports, routers
ovn-nbctl lsp-list prod-web  # ports on this switch
ovn-sbctl show               # which chassis (host) each port is bound to

Removing a switch

Networks → OVN → row → Remove. The switch is dropped from OVN's NB DB; the row in ovn_logical_switches is cleared. Bound LSPs are released first — endpoints stay up but lose their tenant-network connectivity until you re-bind them somewhere.

IPAM pool is preserved

Removing the switch does not delete the IPAM pool that was auto-created with it. Existing leases stay valid for migration / re-bind. Delete the pool from Networks → IPAM if you really want the IPs back.

See also