Dead peer detection

Dead peer detection

[Ryan Whelan]

I thought this conversation had been had in the past, but I can not find it
so forgive me if I'm rehashing something thats been discussed already.

How do you guys detect dead peers?  Actively via a ping or passively via
the 'latest handshake' (once it gets past a certain age, you assume the
peer is offline).  Are their other options?

Re: Dead peer detection

[Matthias Urlichs]

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Hi,
> How do you guys detect dead peers?  Actively via a ping or passively via
> the 'latest handshake' (once it gets past a certain age, you assume the
> peer is offline).  Are their other options?
You can't passively determine that a peer is offline, only that it isn't.
It might just not have anything to send at the moment.

So, yes, ping it.

-- 
-- Matthias Urlichs



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Re: Dead peer detection

[Aaron Jones]

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On 25/05/18 14:50, Ryan Whelan wrote:
> I thought this conversation had been had in the past, but I can
> not find it so forgive me if I'm rehashing something thats been 
> discussed already.
> 
> How do you guys detect dead peers?  Actively via a ping or 
> passively via the 'latest handshake' (once it gets past a certain 
> age, you assume the peer is offline).  Are their other options?

If no traffic is being exchanged, handshakes won't take place either,
so you can't rely on just looking at that.

If you try to communicate with the peer, and the latest handshake is
more than 3 minutes ago, it should be safe to assume the peer is gone;
as handshakes occur (when there's traffic) every 2 minutes.

Note that persistent keep-alive packets count as traffic.

Regards,
Aaron Jones

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