Avoid querying DNS seeds, if we have open connections. #4559

jgarzik commented at 10:44 PM on July 18, 2014: contributor

Possibly we can fiddle with these parameters, e.g. pick "if peers < 4 after 30 seconds, query seed"

jgarzik commented at 5:21 PM on July 19, 2014: contributor

Tweaked,

Want "more than one" peer, to skip DNS seed query (partition)
30 seconds is a long time to pause, and seems likely to trigger human impatience timeouts. Reduced to 10 seconds, then changed to 11 as a post-vacation present for Gavin

in src/net.cpp:None in 9297a48432 outdated

1226 | @@ -1227,6 +1227,18 @@ void MapPort(bool)
1227 |  
1228 |  void ThreadDNSAddressSeed()
1229 |  {
1230 | +    // goal: only query DNS seeds if address need is acute
1231 | +    if ((addrman.size() > 0) &&
1232 | +        (!GetBoolArg("-alwaysdnsseed", false))) {

laanwj commented at 5:33 AM on July 20, 2014:

Maybe call this option '-forcednsseed'?

Diapolo commented at 8:48 AM on July 20, 2014:

@laanwj Agreed, sounds better and easier to understand.

laanwj commented at 5:34 AM on July 20, 2014: member

ACK on concept, haven't tested yet.

laanwj commented at 9:47 AM on July 24, 2014: member

ACK, works great for me, every time

2014-07-24 09:39:07 P2P peers available. Skipped DNS seeding.

sipa commented at 10:00 AM on July 24, 2014: member

Untested ACK; I prefer -forcednsseed as well.

sipa commented at 10:01 AM on July 24, 2014: member

Or what about -dnsseeddelay, which is 11 by default? Setting it to 0 is equal to forcing dns seeding?

laanwj commented at 9:53 AM on July 25, 2014: member

I'm not sure it is an parameter that makes much sense to customize. Usually you'll either want full control over bootstrapping (-dnsseed=0), use DNS seeds when needed after a 'sane' delay (the default), or force DNS seed usage immediately (-forcednsseed, main use case faster debugging/troubleshooting of DNS seeds code).

sipa commented at 2:46 PM on July 27, 2014: member

Fair enough.

Avoid querying DNS seeds, if we have open connections.

The goal is to increase independence and privacy.

2e7009d67b

jgarzik commented at 3:06 PM on July 29, 2014: contributor

Updated to use -forcednsseed, and also updates the --help text.

BitcoinPullTester commented at 3:21 PM on July 29, 2014: none

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laanwj merged this on Jul 29, 2014

laanwj closed this on Jul 29, 2014

laanwj referenced this in commit 4ad23d2110 on Jul 29, 2014

in src/init.cpp:None in 2e7009d67b

 239 | @@ -240,7 +240,8 @@ std::string HelpMessage(HelpMessageMode mode)
 240 |      strUsage += "  -connect=<ip>          " + _("Connect only to the specified node(s)") + "\n";
 241 |      strUsage += "  -discover              " + _("Discover own IP address (default: 1 when listening and no -externalip)") + "\n";
 242 |      strUsage += "  -dns                   " + _("Allow DNS lookups for -addnode, -seednode and -connect") + " " + _("(default: 1)") + "\n";
 243 | -    strUsage += "  -dnsseed               " + _("Find peers using DNS lookup (default: 1 unless -connect)") + "\n";
 244 | +    strUsage += "  -dnsseed               " + _("Query for peer addresses via DNS lookup, if low on addresses (default: 1 unless -connect)") + "\n";
 245 | +    strUsage += "  -forcednsseed          " + _("Always query for peer addresses via DNS lookup (default: 0)") + "\n";

Diapolo commented at 7:51 AM on July 30, 2014:

Nit: This is now missplaced, when considering an alphabetical ordering.

jgarzik deleted the branch on Aug 24, 2014

MarcoFalke locked this on Sep 8, 2021