$re = '~^(\d{1,3}(?:\.\d{1,3}){3})\s*-\s*((?1))\s*-\s*((?:[0-9A-Fa-f]{2}[:-]){3,6}[0-9A-Fa-f]{2})\s*-\s*(\d\d/\d\d/\d{4}\s\d\d(?::\d\d){2}|NEVER EXPIRES|INACTIVE)\s*-\s*(\w)\s*-\s*(.*)$~m';
$str = 'Changed the current scope context to 192.25.200.0 scope.
Type : N - NONE, D - DHCP B - BOOTP, U - UNSPECIFIED, R - RESERVATION IP
============================================================================================
IP Address - Subnet Mask - Unique ID - Lease Expires -Type -Name
============================================================================================
192.25.200.4 - 255.255.255.192- 64-9e-f3-b3-81-d3 -01/08/2018 17:07:46 -D- BH1-WAP-01.local
192.25.200.5 - 255.255.255.192- 50-57-a8-30-11-f6 -01/08/2018 16:24:59 -D- BH1-WAP-03.local
192.25.200.6 - 255.255.255.192- f0-f7-55-df-c4-ff -01/08/2018 16:45:04 -D- BH1-WAP-02.local
192.25.200.7 - 255.255.255.192- 00-23-24-bb-ce-83 -04/08/2018 10:55:00 -D- CESTA1703043.LOCAL
No of Clients(version 4): 4 in the Scope : 192.25.200.0.
Command completed successfully.
Changed the current scope context to 192.25.200.64 scope.
Type : N - NONE, D - DHCP B - BOOTP, U - UNSPECIFIED, R - RESERVATION IP
============================================================================================
IP Address - Subnet Mask - Unique ID - Lease Expires -Type -Name
============================================================================================
192.25.200.68 - 255.255.255.192- 28-94-0f-05-ac-6c -01/08/2018 03:14:46 -D- WAP-C12-01-1047.local
No of Clients(version 4): 1 in the Scope : 192.25.200.64.
Command completed successfully.
Changed the current scope context to 192.28.211.0 scope.
192.28.211.27 - 255.255.255.0 -00-0a-13-00-00-00-00- NEVER EXPIRES -U- CFCameraNearlockers
Changed the current scope context to 192.28.194.0 scope.
192.28.194.254 - 255.255.255.0 -00-48-32-95-85 - INACTIVE -N- bms';
$subst = "$1 ~ $2 ~ $3 ~ $4 ~ $5 ~ $6";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php