When haproxy is configured to track the status of a server using a
server in another backend it will not report all status as expected.
Using substring matching will solve this.
The CSV will output the server status in the following way:
MAINT: MAINT (via pxname/svname)
UP: UP
DOWN: DOWN
Haproxy doc on trach: https://cbonte.github.io/haproxy-dconv/1.8/configuration.html#5.2-track