How do you remember commands ?

[Igris]

So while preparing for RHCSA configuring stratis you need the following in /etc/fsbab

x-systemd.requires=stratisd.service

yet if you do a man on stratisd you wont get that option. On the exam you dont have internet accees so if you forget it how would you proceed ? 

Just forfeit the task and get 0 points for it ? 

[isudoajl]

I have an urgent question, tomorrow I present my exam and I thought it was something typical in the VM's of the RED HAT labs, but I just installed RHEL 8.2 as Guest OS in my own HOST out of curiosity to try the command [ man -k any_word_here ] and I I am realizing that the same thing happens, the output it gives me is: nothing appropriate.

Without being able to use this command I am dead! Do I need to enable something?

[AbhishekGalav]

the -k option relies on man database,
Run mandb command as root user to generate the database and then try man -k <keyword>, it should work

[isudoajl]

Really thank you! Its work!

[DM3]

do "man vdo"

search for fstab

Use the "defaults,x-systemd.requires=vdo.service" and replace "vdo" with "stratisd"

[Armann]

Thanks for all the answers, really helpful as I prepare for the RHCSA.