<Sorry long post, but I do love this stuff>
I had ZERO
linux knowledge before starting, and I only ran into a few hickups, which were easily resolved with a quick search of the AVS site.
I don't know the RS-112, but different models have different upgrade abilities and diff specs.
Series 1 vs Series 2; Amount of Ram (16MB vs 32MB); 1 drive or 2 drives; Tivo StandAlone (SA) or DirecTiVo combo box
The simplest thing to do is to add a hard drive. Get the Hinsdale step by step and read through it a couple of times. If you've taken out drives and understand Primary/Secondary and can set jumper setting for Master/Slave you can easily understand how Linux does it. Also understanding how Linux does its partitions helps, but it's easy to pickup, linux "hda1" is HD,Primary IDE, Master, Partition1, which typically translates to your C Drive.
Although Hinsdale includes many "forks in the road" depending on what type of system you have and what type of HD upgrade you want, for instance, replace a 1 drive system with 1 or 2 drives, keeping or disregarding previous recordings, or simply adding a drive to a single drive system, don't get overwhelmed. I have seen that Weaknees.com has a website that will do a step by step Q&A and then give you a custom (simplified Hinsdale) step-by-step HOW TO for adding a drive. although I have not used it.
I suggest reading though Hinsdale, decide the upgrade path you want, highlight the required passages, ("X" out the others just to be sure) get all the
software that it suggests you "might" need and give it a shot. If possible, it's nice to have a separate Tivo installation PC, preferably with Win98 (there are issues related to Win2000 and XP) and then a separate online PC, if you have questions during the install.
As a precaution against newbie mistakes, I would take the original drives out and keep them as a BACKUP, and install a new single 120GB. If $ allows
I've hacked 2 Sony SAT-T60's (series1 DirectTiVo models) this way, which gives 100+ hours. TiVo can't natively support greater than 137GB drives (real hassle to support >137GB drives) though you can have 2 120's, but when my TiVos with 120s gets full the NowShowing Menu can get kinda slow, and my models have 32MB ram, some models only have 16MB, which are even slower
Up to this point it's more of an upgrade than HACKING
It gets more involve form here on out but the Steve Jenkins How To will guide you and accomplish what you are looking for. It is a GREAT step by step HOW TO
I assume the network card is a TurboNet or TivoNet. I assume you have a router with DHCP that will assign you TiVO a Local IP (You can set up a static IP, but it's just a bit more involved)
Remote contol of the Tivo via TiVoweb (Steve Jenkins how to shows how to set it up), is really a matter of remote access to your home network, which is primarily a matter of security. You DO NOT WANT YOUR TIVO DIRECTLY ACCESSIBLE TO THE INTERNET. Port scans can crash it. and there is no real security solutions for the Tivo itself. I directly connect to my Tivo via VPN connection from my
laptop to my home router or I use XP remote desktop to conect to my home PC and then connect to Tivo. Other more complicated solutions exist.
The best advice is READ READ READ the forums and the Docs mentioned and then take it one step at a time. Don't try and do it all at one time. HD one day and then the hack another, learn the linux stuff and then see if you wanna get into
video extraction (which is why I started) I now have All 9 seasons of Seinfeld with commercials edited out on DVD. I archive PayPer View movies, Lots of stuff for the kids, which is why my 700GB+ of HD storage is almost full

myHTPC is a fantastic frontend for media server.
<WARNING> One work of caution. It relates to what is called the "wife/girl friend factor" I have observed what has been described as an "event bug" which exists in the TiVo software. I have never seen it happen on a Tivo with only a HD upgraded, but have seen it on "hacked" TiVos. Apparently some of the software mods exacerbate the bug, which will causes the Tivo to lock up (while still playing/recording a show) but you can't control the Tivo with the remote or the buttons on the BOX. It requires a REBOOT either via unplugging the unit or logging into the Tivo via Telnet and rebooting via linux command (I had no idea what Telnet was before all this). Wifes/Girlfriends and Children don't like this and get very irritated and will give you grief for messing up their TiVo. I don't know if it is limited to my model as I don't see a lot of people complaing about it, but it happens on mine<END WARNING>
Go for it and have fun.
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