Re: Confused about two development utils

8.8.8.8 is google's public DNS server - yah they can handle whatever you
throw at them but you shouldnt misuse it. The whole point of TTL in DNS is
for suggested caching - you are welcome to ignore it but you are also being
rude to others.

$r->connection->client_ip is the IP your apache server is seeing you come
through which I assume is CloudFlare - I have no idea how to see the real
ip behind cloudflare.

On Tue, Dec 22, 2020 at 7:19 PM Matthias Peng <[email protected]>
wrote:

> Thanks Mithun.
> 1. Since the query is passed through cloudflare, so a CF- header is wanted
> for fetching client's real IP.
> 2. Since I am querying PTR via a stub resolver (such as 8.8.8.8), I guess
> this public dns server has already cached the result. right?
>
> Regards.
>
>
> On Wed, Dec 23, 2020 at 9:08 AM Mithun Bhattacharya <[email protected]>
> wrote:
>
>> Replying to the DL.
>>
>> On Tue, Dec 22, 2020 at 7:07 PM Mithun Bhattacharya <[email protected]>
>> wrote:
>>
>>> $r->connection->client_ip would report your proxy server if you have a
>>> reverse proxy setup - this is not a common use case though.
>>>
>>> DNS lookup would usually be an expensive process and you are supposed to
>>> be nice to other services so cache it for the TTL of the PTR record.
>>>
>>> On Tue, Dec 22, 2020 at 6:44 PM Matthias Peng <[email protected]>
>>> wrote:
>>>
>>>> I am a newbie to mp development stack.
>>>> After one day of work, I have made a simple handler, which returns the
>>>> client's address and its PTR record.
>>>> The demo:
>>>> https://myhostnames.com/
>>>>
>>>> The code shown below:
>>>>
>>>> package MyHostname;
>>>>
>>>>
>>>> use strict;
>>>>
>>>> use Net::DNS;
>>>>
>>>> use Apache2::RequestRec ();
>>>>
>>>> use Apache2::RequestIO ();
>>>>
>>>> use Apache2::Connection ();
>>>>
>>>> use APR::Table ();
>>>>
>>>> use Apache2::Const -compile => qw(OK FORBIDDEN);
>>>>
>>>>
>>>>
>>>> sub handler {
>>>>
>>>>
>>>>     my $r = shift;
>>>>
>>>>     my $ip = $r->headers_in->{'CF-Connecting-IP'} ||
>>>> $r->connection->client_ip;
>>>>
>>>>
>>>>     my $host = dns_query($ip) || "";
>>>>
>>>>
>>>>     $r->content_type('text/plain; charset=utf-8');
>>>>
>>>>     $r->print("Your IP: $ip, Hostname: $host");
>>>>
>>>>
>>>>     return Apache2::Const::OK;
>>>>
>>>> }
>>>>
>>>>
>>>>
>>>> sub dns_query {
>>>>
>>>>     my $ip = shift;
>>>>
>>>>     my $resolver = Net::DNS::Resolver->new();
>>>>
>>>>     my $reply = $resolver->query($ip, 'PTR');
>>>>
>>>>
>>>>     if ($reply) {
>>>>
>>>>         for my $rr ($reply->answer) {
>>>>
>>>>             return $rr->rdstring;  # we need only one
>>>>
>>>>         }
>>>>
>>>>     }
>>>>
>>>>
>>>>     return;
>>>>
>>>> }
>>>>
>>>>
>>>>
>>>> 1;
>>>>
>>>>
>>>>
>>>> Can anyone give your review? Thanks in advance.
>>>>
>>>>
>>>> Matthias
>>>>
>>>>
>>>>
>>>>
>>>> On Tue, Dec 22, 2020 at 1:49 PM Matthias Peng <[email protected]>
>>>> wrote:
>>>>
>>>>> Hello
>>>>>
>>>>> I am developing a simple mp2 application.
>>>>> I looked for the installation for mp2 utils, and found this two:
>>>>>
>>>>> libapache2-mod-perl2
>>>>>
>>>>> libapache2-mod-apreq2
>>>>>
>>>>>
>>>>> what're their relations? Should I install both, or only the first one?
>>>>>
>>>>>
>>>>> Thanks.
>>>>>
>>>>