using both ConnectTo and AutoConnect to avoid network partitions

Nirmal Thacker
Tue, 22 Aug 2017 22:19:18 -0000

Hi Guus

Thanks for clarifying. Some follow up questions:

- How do we patch 1.1pre14 with this fix? Or will there be a 1.1pre15 to
upgrade to?
- What is the workaround until we patch with this fix? Using a combination
of AutoConnect and ConnectTo?
- When we use ConnectTo, is it mandatory to have a cert file in the hosts/*
dir with an IP to ConnectTo ?


   -nirmal

On Tue, Aug 22, 2017 at 12:10 PM, Guus Sliepen <guus at tinc-vpn.org>
wrote:

> On Mon, Aug 21, 2017 at 05:37:06PM -0700, Nirmal Thacker wrote:
>
> > Today our Tinc network saw a network partition when we took one tinc
node
> > down.
> >
> > We knew there was a network partition since the graph showed a split.
> This
> > graph is not very helpful but its what I have at the moment:
> >
> > http://i.imgur.com/XP2PSWc.png
>
> The graph is very clear.
>
> > Some questions:
> > - should we have a combination of both ConnectTo and AutoConnect to
avoid
> > such a network split?
>
> No, it's a bug in AutoConnect. I've just pushed a fix to the 1.1
branch
> that will try to continue to connect to unreachable nodes, even if a
> node already has 3 or more connections.
>
> > - Say we have 3 ConnectTo variables and then AutoConnect=yes, would
there
> > ever be more than 3 connections ? (I read somewhere that AutoConnect
will
> > make upto 3 connections only)
>
> There can always be more than 3 connections, even when AutoConnect is
> enabled.
>
> When starting, tinc will try to make outgoing connections to all nodes
> listed in ConnectTo statements. This can be more than 3 nodes. After
> that, the AutoConnect algorithm kicks in.
>
> The AutoConnect algorithm tries to regulate the number of established
> connections, either by creating more outgoing connections, or by
> closing connections that it made itself. It will never close incoming
> connections, and it also won't close outgoing connections to a node
that
> isn't already connected to at least one other node.
>
> Ideally, after a while connections get rearranged such that no node has
> more than 3 connections. But this can take a while, or it might never
> happen; for example if you have 5 nodes behind NAT, and one public node,
> then the public node will always have 5 connections.
>
> --
> Met vriendelijke groet / with kind regards,
>      Guus Sliepen <guus at tinc-vpn.org>
>
> _______________________________________________
> tinc mailing list
> tinc at tinc-vpn.org
> https://www.tinc-vpn.org/cgi-bin/mailman/listinfo/tinc
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://www.tinc-vpn.org/pipermail/tinc/attachments/20170822/bf08c61c/attachment.html>