I just finished doing mine. For the 1st time in 7 yrs we had hot water odor.
I turned off elec and propane to the water heater. Opened faucet to run cool water thru it for about 5 minutes to cool it. Switched the water bypass switch. Pulled the anode rod (Surburban). Used a flush wand to flush out the tank. Poured some bleach in the anode rod hole using a piece of folded foil for a funnel. New anode rod in. Put the bypass switch back to normal to fill the tank. Opened each hot water faucet until I could smell chlorine, then closed. Let it set for a couple hours.
Bypassed water heater again. Pulled anode rod to drain tank. Flushed again with wand. Rod back in. Bypass back to normal to fill tank. Run each faucet until no chlorine odor.
No more hot water odor.