My friend was asked to do network penetration testing for a client who has 1500 ip's

Hi I am an intern at security company which mainly do web and mobile pentest, this question is for my friend his company asked him to do network pentest for their client onsite for their 1500 IP's.
Automated test and manual both.
Currently he is at automated test stage and next he is asked to do manual pentest on those 1500 ip.
He is facing issue in manual testing, as he this is his first network PT and he is …

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