Maintained by: NLnet Labs

error: outgoing tcp: bind: Address already in use

Quirin Scheitle
Thu Jul 6 10:32:45 CEST 2017

Hi Nick,

IIRC, unbound does a “bind before connect” on sockets, which requires a local port to be completely unused [1] to be used by bind. 

Unbound 1.6.4 should fix this by setting SO_REUSEADDR on outgoing ports - please give it a try.

Kind regards


> On 06 Jul 2017, at 10:13, Nick Urbanik via Unbound-users <unbound-users at> wrote:
> Dear Folks,
> A DNS server running unbound 1.6.3 has these messages; any suggestions
> on what is happening?
> error: serviced_tcp_initiate: failed to send tcp query
> error: outgoing tcp: bind: Address already in use
> -- 
> Nick Urbanik 808-71011 nick.urbanik at
> GPG: 7FFA CDC7 5A77 0558 DC7A 790A 16DF EC5B BB9D 2C24  ID: BB9D2C24
> I disclaim, therefore I am.

Dipl.-Ing. Quirin Scheitle		    		Web:
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