table.lookup_backend

BACKENDtable.lookup_backendIDidSTRINGkeyBACKENDdefault

Looks up the key key in the table id. When the key is present, its associated value will be returned. When the key is absent, the default value is returned. The default value is required.

Just as for the req.backend variable, both backend names and director names may be specified.

Example

backend b0 { .host = "203.0.113.0"; }
backend b1 { .host = "203.0.113.1"; }
backend b2 { .host = "203.0.113.2"; }

director d0 random {
  { .backend = b0; .weight = 1; }
  { .backend = b2; .weight = 1; }
}

table t BACKEND {
  "a.example.com": b0,
  "b.example.com": b1,
  "c.example.com": d0,
}

sub vcl_recv {
  set req.backend = table.lookup_backend(t, req.http.host, req.backend);
}

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