Within the Red Hat certification program, the RHCA is considered the most complete (and grueling) certification among the seven major Red Hat certifications. In fact, some equate the prestige of the RHCA to that of the Microsoft Certified Master and possibly the CCIE.
A plumbing fixture like a sink can not function properly without a sink vent. When a drain pipe drains it creates a negative pressure in the sink drain; the negative pressure will pull the water out of the p-trap of the sink that's draining and sewer gases can enter your home if a sink vent is not installed.
Leaking P-traps can damage the floor or the sink cabinet. The pipes under your kitchen sink can look daunting, especially if you have two sinks, but replacing them isn't difficult, even if you have little plumbing experience. The curved pipes, which are called P-traps, connect to the sink drain and waste lines by compression fittings, and you can often unscrew these without a tool.