You do not have to be connected to the internet in order to record say FOH of a live gig.  Anything that requires it should be avoided.
 
All you have to do is take one of those Zoom recorders out, patch the line inputs to a spare set of outputs from your desk.
 
Or run a simple program on a laptop such as Studio One capture with a stereo input interface to do the same thing.  If you want to get serious about multitrack live recordings then get yourself a Presonus live digital mixer that hooks up to laptop running Capture.  All very straight forward.

I thought you might have a Zoom H2N. This is the one I have and it is excellent. It's in a pouch and it has 4 built in mics which all sound excellent.  It is the ultimate thing for capturing off the cuff audio really.  It beats all other options.   All you have to do is make sure the batteries are good and it seems to go forever on a set of batteries. Carry spares.  And ensure you have enough audio record room. I have a 16 Gig card in mine. So plenty of record time.
 
It can also be put into 4 channel mode and it makes an amazing front rear recording at the same time.  A very wide range of sounds can be recorded from ultra soft to loud. Super easy to transfer the files too.  It has line inputs and with the appropriate lead it could also record FOH from any mixer as well. Along as the whole mix is in the FOH mixer that is.
 
I recently went overseas to Asia and captured the whole thing and came back with 6 Gig or so of live recordings. The quality is ridiculous and what I got was awesome. Cannot believe it. Fast trains in Singapore to crowded malls in Penang etc.. Outside atmos effects. All on this tiny thing that you can have in your pocket.  Also it is wise to not be obvious you are recording either.  You can hold this in your hand carefully and quietly and just walk along for example with your hands down by your side and one hand is holding the recorder.  Not obvious. You get more natural sounding occurrences then.  Especially when people are involved. 
 
Part of the recordings are the sound of my son playing drums on a cruise ship.  We went on a cruise on his ship.  They did shows but also intimate jazz gigs up in the Jazz bar.  I had the zoom sitting on a table about 3 to 4 meters away from the band and it recorded the whole ensemble beautifully. It was all acoustic and they played in perfect balance. The recording sounds amazing. Like a well mixed multitrack. Back to the old days of a mic in a room! No one knew it was happening either.  In Singapore we went to a super trees demo outside on a beautiful night.  It was an amazing light show specular type of event.  The soundtrack was huge and loud.  The recording I did sounds like you are actually there.  It is huge and loud and epic! Some of it is in 4 channel surround. When played back on 4 speakers it sounds breathtaking. 
 
I am dropping segments of these things into synths like Serum and build interesting wavetables. Once you do that you can sweep the wavetables and make incredible sounding patches. 

I bought a Zoom H2n used pretty cheap (haven't received it yet.)  This looks like a very versatile product.  I don't know that I will bother connecting it to my Surface, other than for testing.  The only real benefit I can see from that is that the Surface would be like a remote control and I could see the signal levels clearly while recording.  But it may not be worth the trouble, as easy as the Zoom recorders are to use.
One thing that slightly troubles me is that Zoom doesn't quote frequency specs for their Zoom capsules.  Somewhere I saw somebody state them as 70-18,000.  If there is a big drop-off under 70, that would be missing a lot.  I notice the Yeti Pro is quoted as 20-20,000.
I have the Zoom H6, which I believe use the same capsules that are in the Y4n and Y2n.  I know I get lots of sound below 70 Hz, but I don't know how it tapers.  In practice, I mainly would look for bass trombone or tuba, so 45 Hz is about the bottom for me.  I expect there will be enough to pull it up with EQ.  If it is a big problem, my plan B will be a Yeti Pro.
Can anybody provide any practical guidance about the "2-channel surround" (which seems like an oxymoron) and the "4-channel surround" on the H2n?  I assume that "2-channel surround" simply means that we pick up 360 degrees of sound, but present it as stereo with clear left-right separation.