from PHP, how I can detect visitior using IPv6 ?

[000]

Hi,

I read: User with an IPV6 IP can't load website


Then . . .

using PHP, how we can detect if visitor is using IPv6 ?

<?PHP
if($_SERVER['REMOTE_ADDR'] != ???) . . .

how is the REGEX ?

 

[cPanelChris]

Hello @000 ,

Something like the following should work to check what protocol an IP is.

<?php
$ip = "255.255.255.255";
//$ip = "FE80:0000:0000:0000:0202:B3FF:FE1E:8329";

if(filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4)) {
    echo "IPv4\n";
} else if(filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV6)) {
    echo "IPv6\n";
} else {
    echo "Invalid IP\n";
}

 

[000]

Many thanks Chrish

Then if we have RECORD in data base as

column_ip_client = varchar 15

that is WRONG ?
Any day, any hour our web can go visited by

FILTER_FLAG_IPV6

?

 

[cPanelChris]

Hello @000 ,

An IPv6 IP address can contain up to 39 characters including the semicolons. As such, a varchar of length 15 would not be guaranteed to be able to hold the IP. If the IP exceeds 15 characters, only the first 15 characters would be stored. This is documented at the link below.

MySQL :: MySQL 5.7 Reference Manual :: 11.3.2 The CHAR and VARCHAR Types

dev.mysql.com

 

[000]

An IPv6 IP address can contain up to 39 characters...

Oh,
thanks again.Then many code around Internet is broken! ...

Oh god ...