Get a PDU or metered PDU on a dedicated breaker.
You can get either 120v or 240v PDU, but I would recommend getting 240v as almost all PSU allow both 120/240v usage. You many need to invest in C13 to C14 cables.
Example of 240v 30a pdu (240 x 30 = 7200 watts less 20% = 5760 usable watts).
You'll need an outlet for the dedicated breaker that looks like one one below.
https://www.amazon.com/gp/product/B00002NAT9/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1
I have both 120v and 240v metered pdus.