controlller

LAX, an air traffic control tower, does not employ ERAM. Los Angeles Center (ZLA), the overlying air route traffic control center, does.

Note that this most recent outage (NOTAMs) had nothing to do with ERAM.

ERAM is employed the the 23 air route traffic control centers [1] throughout the nation as their primary operating system. If there were a system-wide outage of ERAM, the consequences would be magnitudes more consequential than any NOTAM outage. Basically every flight in the air and not close to a terminal facility would lose radar contact and controllers would be working blind, causing widespread chaos and likely many safety incidents. Non-radar air traffic control is a thing, but generally controllers do not have adequate training or currency to do it safely, and definitely not at anywhere near normal capacity.

[1] https://123atc.com/facilities#centers