Clarify docs for requirements/handling of addnode/connect nodes

src/init.cpp

@@ -369,11 +369,11 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageOpt("-txindex", strprintf(_("Maintain a full transaction index, used by the getrawtransaction rpc call (default: %u)"), DEFAULT_TXINDEX));
 
     strUsage += HelpMessageGroup(_("Connection options:"));
-    strUsage += HelpMessageOpt("-addnode=<ip>", _("Add a node to connect to and attempt to keep the connection open"));
+    strUsage += HelpMessageOpt("-addnode=<ip>", _("Add a node to connect to and attempt to keep the connection open (see the `addnode` RPC command help for more info)"));
     strUsage += HelpMessageOpt("-banscore=<n>", strprintf(_("Threshold for disconnecting misbehaving peers (default: %u)"), DEFAULT_BANSCORE_THRESHOLD));
     strUsage += HelpMessageOpt("-bantime=<n>", strprintf(_("Number of seconds to keep misbehaving peers from reconnecting (default: %u)"), DEFAULT_MISBEHAVING_BANTIME));
     strUsage += HelpMessageOpt("-bind=<addr>", _("Bind to given address and always listen on it. Use [host]:port notation for IPv6"));
-    strUsage += HelpMessageOpt("-connect=<ip>", _("Connect only to the specified node(s); -connect=0 disables automatic connections"));
+    strUsage += HelpMessageOpt("-connect=<ip>", _("Connect only to the specified node(s); -connect=0 disables automatic connections (the rules for this peer are the same as for -addnode)"));
     strUsage += HelpMessageOpt("-discover", _("Discover own IP addresses (default: 1 when listening and no -externalip or -proxy)"));
     strUsage += HelpMessageOpt("-dns", _("Allow DNS lookups for -addnode, -seednode and -connect") + " " + strprintf(_("(default: %u)"), DEFAULT_NAME_LOOKUP));
     strUsage += HelpMessageOpt("-dnsseed", _("Query for peer addresses via DNS lookup, if low on addresses (default: 1 unless -connect used)"));

src/rpc/net.cpp

@@ -201,6 +201,8 @@ UniValue addnode(const JSONRPCRequest& request)
             "addnode \"node\" \"add|remove|onetry\"\n"
             "\nAttempts to add or remove a node from the addnode list.\n"
             "Or try a connection to a node once.\n"
+            "Nodes added using addnode (or -connect) are protected from DoS disconnection and are not required to be\n"
+            "full nodes/support SegWit as other outbound peers are (though such peers will not be synced from).\n"
             "\nArguments:\n"
             "1. \"node\"     (string, required) The node (see getpeerinfo for nodes)\n"
             "2. \"command\"  (string, required) 'add' to add a node to the list, 'remove' to remove a node from the list, 'onetry' to try a connection to the node once\n"