disabling cache; it's not really necessary.

tunnelbroker/errs.go

@@ -0,0 +1,12 @@
+package tunnelbroker
+
+import (
+	`errors`
+)
+
+var (
+	ErrBadPrefixValue error = errors.New("cannot reliably determine a TunPrefix or netip.Prefix from value")
+	ErrHERateLimit    error = errors.New("the Hurricane Electric soft rate limit has been hit; please lower your frequency or you will get a 429")
+	ErrHENoTuns       error = errors.New("no tunnel configuration found for the specified tunnel ID")
+	ErrHEInvalid      error = errors.New("the new client IP address is either not allowed or cannot be pinged")
+)