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Homelab Brief - Hardening MCP Servers: Auth and Transport · Big Iron Radio

• 0:02
  Welcome to the Homelab Brief from Big Iron.
• 0:06
  Today, hardening MCP servers once they stop being local subprocesses and become real network services.
• 0:14
  Quick note, this is an AI voice drawn from a Big Iron guide.
• 0:19
  Links below.
• 0:20
  Default position first.
• 0:23
  A SDDO subprocess MCP server is the safe one.
• 0:26
  The server runs as a child process of the client.
• 0:30
  Nothing's on the network, nothing to attack.
• 0:33
  Only move to SSE or streamable HTTP transport when you have a real multi-client, multi-machine need.
• 0:41
  Don't expose it just because you can.
• 0:43
  The moment you do go network.
• 0:46
  Bind to a tailnet or a VLAN scoped interface only never zero, zero, zero, zero, and then enforce that same scoping at the firewall too.
• 0:55
  Two layers, because a bind setting is one config typo away from wide open.
• 1:00
  Authenticate regardless of network topology.
• 1:04
  For variable human identities behind an existing identity provider, use OAuth2, one with PKCE.
• 1:11
  For a small fixed set of machine identities, use MutualTLS.
• 1:15
  And a bearer token is an acceptable floor for a single operator setup.
• 1:21
  Pick per your situation, but pick something.
• 1:24
  Here's the mental model people get wrong.
• 1:26
  Being on your tailnet or VLAN is network reachability, not authentication.
• 1:32
  Both layers are required, and neither substitutes for the other.
• 1:36
  It's on my private network is not a login.
• 1:38
  And authentication alone still isn't enough in force per client tool allow lists, ideally at a gateway, so a given client can only call the tools it should.
• 1:49
  Reachable, authenticated, and scoped all three.
• 1:52
  The full hardening checklists in the show notes.
• 1:55
  That's your brief.