The best way to do sports indoors is to manually adjust the exposure. You have the most complete control over shutter speed, aperture and ISO.
Note that manual exposure is more accurate than automatic exposure metering of flickering lights found in most indoor sports venues and outdoor stadiums used at night. The meter often measures the lights at their peak and then the shutter opens when in the valley of its cycle and vice versa. If you set the manual exposure for the middle of the light cycle, you will be closer to the overall picture.
If you want to get close to freezing the action, all you have to do is live with the flickering of the lights. In order to eliminate most of the flicker, you would need to use shutter speeds of at least 1/125 second, which is not the case with ice hockey. When you get the shots you want to take in raw mode, you have more latitude to correct the color and exposure of the light peaks and valleys during post-processing. (The linked question refers to the processing of hockey photos taken under constraints, which gives an example of the strength of raw post-processing compared to JPEG.)
Of course, the number of frames that you can record in a burst is reduced before the buffer fills and the frame rate drops. With the 6D, you can record about 17 raw images continuously before slowing down. At 4.5 fps (theoretically), this corresponds to a four-second burst. Normally you should avoid filling the buffer completely. Try to limit the number of outbreaks to half, so you have a few shots in reserve when a key moment occurs.
You can set a custom white balance by shooting directly onto a solid white piece of ice. Underexposure one or two apertures intentionally, set the focus switch on the lens to "MF" and defocus either on the MFD or at infinity. If the lights on the venue are flickering (they probably will – our eyes can not tell the difference, but our cameras can!), Take multiple shots and use a shot that's roughly halfway between the brightest and the darkest to set the custom white balance.
Custom White Paper Note: When you are taking raw pictures and want to use a custom white paper in the post by using Canon Digital Photo Professional raw conversion software you Got to When you take the picture, load that custom white balance and set the white balance to Custom. You can still change the white balance to another available setting (Auto, Color Temp, White Balance, and so on). However, if the WB setting in the camera is set to a value other than Custom, you can not apply the custom WB value generated from another shot of a meaningless white object under the lighting conditions in question. You can probably get very close with the Click WB tool and WB Fine Tuning along the blue-yellow and magenta-green axes, but it will not be exactly the same.
Do not forget to set the lens back to "AF" when you have adjusted the white balance. Set the image stabilizer to "On", the IS mode to "2" (panning mode) and the focus limiter to "2.5 m – ∞" (unless your subjects are closer to you than 2.5 meters at points in action).
With a 6D full screen and the superb EF 70-200mm 1: 2.8 L IS II you will only get a lot of close shots if the players are on the parts of the ice you are on. If you want to trim footage from players at a greater distance, your maximum shutter speeds will need to be shorter to control the subject's motion blur than would be the case with uncropped footage.
With the 6D's AF system, you probably want to manually select and leave only the center AF point. Set the AF mode to AI servo AF, You must leave your main subject in the center of the picture. When shooting remotely, you're probably going to trim a little anyway, so you can customize the composition if you wish by cropping off-center. When you set the AF point to automobile You will end up with the next thing in the frame (usually a Plexiglas support) instead of your intended subject in focus. When filming I prefer the AF ON Button to activate the AF and disable the AF associated with the shutter, but it takes some getting used to. YMMV.
Set the drive mode continuous,
Set the aperture to 1: 2.8, set the shutter speed to 1/1000, and then set the ISO value until you see a decent histogram on the back of the camera when you review your shots. Avoid the ISO settings for +1 / 3 stop on Canon DSLRs. Remember to move the histogram slightly to the right when shooting at a downward angle where most of the frame is white ice. If you are photographing from a very low angle, such as the team bench, and much of the frame has a dark background (such as dimly lit seating areas), you want the histogram to be displayed farther left. If you are forced to a higher ISO value by 1/1000 second than you are willing to accept, reduce the shutter speed to 1/800, 1/640 or 1/500 second and check your results. When you check your shots on the LCD, you zoom in to see if motion blur is occurring.
Do not be afraid to take many pictures. Under the best of circumstances, the "keeper" rate in sports is lower than most other types of photography. But that does not mean that you should not plan your recordings, instead of just "praying and spraying". It just means that you should accept that the action sometimes develops differently than expected. Sometimes the AF will miss something. Sometimes it will miss a land mile. Sometimes another player (or, more likely, a referee with his back to you) comes in between the moment you and your subject with the shutter open.