funcGetDERPMap¶added inv1.72.0

func GetDERPMap() *tailcfg.DERPMap

GetDERPMap returns a fallback DERP map that is always available, useful for basicbootstrapping purposes. The dynamically updated DERP map in LocalBackend shouldalways be preferred over this. Use this DERP map only when the control plane isunreachable or hasn't been reached yet. The DERP servers in the returned map alsorun a fallback DNS server.

funcMakeLookupFunc¶added inv1.40.0

func MakeLookupFunc(logflogger.Logf, netMon *netmon.Monitor) func(ctxcontext.Context, hoststring) ([]netip.Addr,error)

MakeLookupFunc creates a function that can be used to resolve hostnames(e.g. as a LookupIPFallback from dnscache.Resolver).The netMon parameter is optional; if non-nil it's used to do faster interface lookups.

funcSetCachePath¶added inv1.32.0

func SetCachePath(pathstring, logflogger.Logf)

SetCachePath sets the path to the on-disk DERP map cache that we store andupdate. Additionally, if a file at this path exists, we load it and merge itwith the DERP map baked into the binary.

This function should be called before any calls to UpdateCache, as it is notconcurrency-safe.

funcUpdateCache¶added inv1.32.0

func UpdateCache(c *tailcfg.DERPMap, logflogger.Logf)

UpdateCache stores the DERP map cache back to disk.

The caller must not mutate 'c' after calling this function.