$re = '/\/[^\/]*\/[^\/]*\/[^\/]*\/(?<VMX>[^\.]*)\.vmx/m';
$str = '<166>2020-09 Hostd: info hostd[2099648] [Originator@6876 sub=Vmsvc.vm:/vmfs/volumes/5b33d479-61618708-d3cd-d094665b5e96/Burp-Collab/Burp-Collab.vmx opID=1bcac8c3 user=root] Send config update invoked
<13>2020-09-08T05:55:17Z vmauthd[6101123]: /vmfs/volumes/5b33d479-61618708-d3cd-d094665b5e96/Qualys_scanner_RPA/Qualys_scanner_RPA.vmx: Connected to mks-fd, remote end sent pid: 5240594
<164>2020-09-11T13:00:51.278Z Hostd: warning hostd[2099584] [Originator@6876 sub=Vmsvc.vm:/vmfs/volumes/5b33d479-61618708-d3cd-d094665b5e96/SIE-PT-BAU-1/SIE-PT-BAU-1.vmx] Failed to find activation record, event user unknown.
<166>2020-09-08T05:54:57.060Z Hostd: info hostd[2099583] [Originator@6876 sub=Vmsvc.vm:/vmfs/volumes/5b33d479-61618708-d3cd-d094665b5e96/SIE-PT-BAU-2Kali/SIE-PT-BAU-2Kali.vmx opID=1bca6b2a user=root] Ticket issued for mks service to user: root
from here only bold letter which are vm i want to extract';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
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