See discussion in #6636.
Currently, an implementation detail leaks here:

>  "minping": 9223372036854.775,

This is `std::numeric_limits<int64_t>::max()` milliseconds, or approximately 300,000 years. What we really want to communicate here is that the information is missing. So it would be better to report it as `null`.

>  "minping": null,

{
    if (fHelp || params.size() != 0)
        throw runtime_error(
                            "listbanned\n"
                            "\nList all banned IPs/Subnets.\n"
                            "\nExamples:\n"
                            + HelpExampleCli("listbanned", "")
                            + HelpExampleRpc("listbanned", "")
                            );
    banmap_t banMap;
    CNode::GetBanned(banMap);
    UniValue bannedAddresses(UniValue::VARR);
    for (banmap_t::iterator it = banMap.begin(); it != banMap.end(); it++)
    {
        CBanEntry banEntry = (*it).second;
        UniValue rec(UniValue::VOBJ);
        rec.push_back(Pair("address", (*it).first.ToString()));
        rec.push_back(Pair("banned_until", banEntry.nBanUntil));
        rec.push_back(Pair("ban_created", banEntry.nCreateTime));
        rec.push_back(Pair("ban_reason", banEntry.banReasonToString()));
        bannedAddresses.push_back(rec);
    }
    return bannedAddresses;
}
UniValue clearbanned(const UniValue& params, bool fHelp)