F5 CLI commands

Might be worth starting here https://support.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/tmos_management_guide_10_1.html https://support.f5.com/content/kb/en-us/products/big-ip_ltm/manuals/product/bigip_tmsh_refguide/_jcr_content/pdfAttach/download/file.res/Traffic_Management_Shell_(tmsh)_Reference_Guide.pdf

What do you mean by useful ? Useful only depends on what you're wanting to do.

Most used for myself

list ltm virtual list ltm pool show net self-ip

(To name but a few...)