wcl block
Mounts a host folder into a guest — over virtiofs when host and guest support it, falling back to SMB served by the lab daemon at the segment gateway.
A share {} exposes a host folder to a guest. The default transport = "auto" uses virtiofs (a vhost-user-fs device — no guest networking involved, snapshot-safe) when both the host and the guest profile support it, and falls back to SMB served by the lab daemon at the segment gateway (\\<gateway>\<share>) otherwise; pin transport = "virtiofs" or "smb" to force one. SMB credentials are auto-generated per lab and persisted in .vmlab/smb/creds (rotated only by destroy). The guest agent mounts the share once the VM is ready — Linux mounts the virtiofs tag directly, Windows mounts it via WinFsp.
share { host = "./src" guest = "/mnt/src" } // auto-mounted when ready
share { host = "~/data" guest = "D:\\data" readonly = true } // drive letter on Windows
share { host = "./old" guest = "X:" smb1 = true } // legacy SMB1 for XP/2003
share { host = "./out" guest = "/mnt/out" transport = "smb" } // force a transport
// `name = "..."` is optional (derived from the guest path if omitted)
Share contents live on the host and are outside snapshot scope. The SMB path requires a NIC on a segment, and so does the default transport = "auto" (it can still fall back to SMB at VM start) — a validation error otherwise. Only an explicit transport = "virtiofs" shares into a machine with no NICs at all. On Windows the agent mounts as SYSTEM (visible to provisions and vmlab exec); with SMB, interactive users double-click the auto-dropped vmlab-shares desktop script once to authenticate their own session. Container volume {} blocks ride the same virtiofs transport (CIFS fallback) — see the container block.