From: Eric Voskuil <eric@voskuil.org>
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Date: Thu, 15 Mar 2018 10:17:22 +0100
Message-Id: <8C660724-A76D-44C1-9140-AD3215768CE1@voskuil.org>
References: <e2fd3226-91ff-d0ca-67c7-2c4a98c6628f@voskuil.org>
	<620d4b5e-61c4-4501-9787-c73109908418@achow101.com>
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To: Andrew Chow <achow101-lists@achow101.com>,
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] version.relay behavior change
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Thanks for the reply Andrew. I=E2=80=99ve reviewed the relevant Core sources=
 and I do not see any problem. We have also synced against a Core node local=
ly and not seen the problem.

The reason I suspected it was Core is that it is very common and all of the U=
ser Agents are consistent (with an occasional exception for forked nodes). S=
o there=E2=80=99s no easy way to determine what sort of nodes we are seeing.=
=20

We tend to cycle through many more connections during sync than a Core node,=
 so may just be seeing it more frequently, but I assume Core would log this b=
ehavior as well. Even so, seeing that wouldn=E2=80=99t help much. I=E2=80=99=
m as certain as I can be at this point that we are setting the flag and vers=
ion correctly (and that we do not set bip37 filters).

This behavior started infrequently with 0.14.0 peers and has become more com=
mon over time. Just wondering at this point what fork would report as Core a=
nd be that common? We used to drop peers that did this (for protocol noncomp=
liance), and I=E2=80=99m considering reinstating that behavior.

e

> On Mar 9, 2018, at 16:33, Andrew Chow via bitcoin-dev <bitcoin-dev@lists.l=
inuxfoundation.org> wrote:
>=20
> Looking through the code, I don't think that this behavior has changed. Ar=
e you sure that you are actually connected to Satoshi:0.15.0 nodes and not a=
 node that has simply set their user-agent to that (i.e. not a real Satoshi:=
0.15.0 node)?
>=20
> If what you are seeing is true, it is likely a bug and not an intentional c=
hange. In that case, can you provide specific details on how to reproduce?
>=20
> Andrew
>=20
>> On 03/09/2018 02:50 AM, Eric Voskuil via bitcoin-dev wrote:
>> /Satoshi:0.15.0/ and later nodes appear to be no longer honoring the
>> version.relay=3Dfalse flag (BIP37). Could someone familiar with the chang=
e
>> please explain the rational?
>>=20
>> Thanks,
>>=20
>> e
>>=20
>>=20
>>=20
>> _______________________________________________
>> bitcoin-dev mailing list
>> bitcoin-dev@lists.linuxfoundation.org
>> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>=20
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev

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<html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=3D=
utf-8"></head><body dir=3D"auto"><div></div><div>Thanks for the reply Andrew=
. I=E2=80=99ve reviewed the relevant Core sources and I do not see any probl=
em. We have also synced against a Core node locally and not seen the problem=
.</div><div><br></div><div>The reason I suspected it was Core is that it is v=
ery common and all of the User Agents are consistent (with an occasional exc=
eption for forked nodes). So there=E2=80=99s no easy way to determine what s=
ort of nodes we are seeing.&nbsp;</div><div><br></div><div>We tend to cycle t=
hrough many more connections during sync than a Core node, so may just be se=
eing it more frequently, but I assume Core would log this behavior as well. E=
ven so, seeing that wouldn=E2=80=99t help much. I=E2=80=99m as certain as I c=
an be at this point that we are setting the flag and version correctly (and t=
hat we do not set bip37 filters).</div><div><br></div><div>This behavior sta=
rted infrequently with 0.14.0 peers and has become more common over time. Ju=
st wondering at this point what fork would report as Core and be that common=
? We used to drop peers that did this (for protocol noncompliance), and I=E2=
=80=99m considering reinstating that behavior.</div><div><br></div><div>e</d=
iv><div><br>On Mar 9, 2018, at 16:33, Andrew Chow via bitcoin-dev &lt;<a hre=
f=3D"mailto:bitcoin-dev@lists.linuxfoundation.org">bitcoin-dev@lists.linuxfo=
undation.org</a>&gt; wrote:<br><br></div><blockquote type=3D"cite"><div>
 =20
    <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3Dutf-8"=
>
 =20
 =20
    <p>Looking through the code, I don't think that this behavior has
      changed. Are you sure that you are actually connected to
      Satoshi:0.15.0 nodes and not a node that has simply set their
      user-agent to that (i.e. not a real Satoshi:0.15.0 node)?</p>
    <p>If what you are seeing is true, it is likely a bug and not an
      intentional change. In that case, can you provide specific details
      on how to reproduce?</p>
    <p>Andrew<br>
    </p>
    <br>
    <div class=3D"moz-cite-prefix">On 03/09/2018 02:50 AM, Eric Voskuil
      via bitcoin-dev wrote:<br>
    </div>
    <blockquote type=3D"cite" cite=3D"mid:e2fd3226-91ff-d0ca-67c7-2c4a98c662=
8f@voskuil.org">
      <pre wrap=3D"">/Satoshi:0.15.0/ and later nodes appear to be no longer=
 honoring the
version.relay=3Dfalse flag (BIP37). Could someone familiar with the change
please explain the rational?

Thanks,

e

</pre>
      <br>
      <fieldset class=3D"mimeAttachmentHeader"></fieldset>
      <br>
      <pre wrap=3D"">_______________________________________________
bitcoin-dev mailing list
<a class=3D"moz-txt-link-abbreviated" href=3D"mailto:bitcoin-dev@lists.linux=
foundation.org">bitcoin-dev@lists.linuxfoundation.org</a>
<a class=3D"moz-txt-link-freetext" href=3D"https://lists.linuxfoundation.org=
/mailman/listinfo/bitcoin-dev">https://lists.linuxfoundation.org/mailman/lis=
tinfo/bitcoin-dev</a>
</pre>
    </blockquote>
    <br>
 =20

</div></blockquote><blockquote type=3D"cite"><div><span>____________________=
___________________________</span><br><span>bitcoin-dev mailing list</span><=
br><span><a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org">bitcoin-de=
v@lists.linuxfoundation.org</a></span><br><span><a href=3D"https://lists.lin=
uxfoundation.org/mailman/listinfo/bitcoin-dev">https://lists.linuxfoundation=
.org/mailman/listinfo/bitcoin-dev</a></span><br></div></blockquote></body></=
html>=

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