Current system machines.
Master Backend: mythzues
Updated 11/02/2007 - Actual update took all weekend until most bugs were worked out. New - Athlon X2 BE-2350 45W Gigabyte GA-M61P-S3 has 4 PCI slots and 4 SATA CODEGEN 4U-500-CA Black 4U rackmount case 1 GB DDR2 REPLACED BY ABOVE - Old pIII-933 MHz bought for $65 a few years ago. 2 - PVR 500s for a total of 4 tuners recording from cable 80 GB OS drive with 10 GB for system and 70GB for something else. 250 GB harddrive for videos 500 GB harddrive for tv recording 500 GB drive for more tv recording using storage groups in svn.
Slave Backend 1: mythares
Updated 11/02/2007 - Same note from mythzues above applies here. Old pIII-933 MHz bought for $65 a few years ago. REPLACED BY ABOVE - EPIA 5000 board - This board served up the disk space just fine, but was dog slow for transcoding. 160 GB harddrive contains photos, music and misc. /myth directories Runs DHCP and NFS mounts for diskless frontends. Also transcodes and commflags.
Slave Backend 2: apollo
Athlon XP-M 2400+ my desktop machine running gentoo 160 GB used for videos and some childrens tv backups. Runs commflagging and transcoding processes because the master backend has issues recording 4 shows, serving up recorded shows and trying to commflag.
Frontend 1: mythjester
Athlon-XP 2400+ underclocked to 1600 MHz Network boot and contains a DVD drive for playing DVDs
Frontend 2: mythvenus
Old 933MHz PIII in a fancy black desktop case Network boot. The kids machine for movies and tv playback.
Frontend 3: mythhades
Asus Pundit-P1 AH2 Network boot and contains a DVD drive for playing DVDs Newest and flashiest frontend yet. Now the primary frontend in the family room
Eventually all frontends will have flash drives to remove remote boot limitations. Also, all frontends will run commflagging and transcoding jobs in the late night early morning to spread that load out and complete the jobs more quickly. I like to transcode everything to maximize storage and remove commercials for the kids.
Ramblings of a mad mythtv user: I have been lurking on mythtv website and mailing lists since mid - 2002. I started, in December 2003, with my linux desktop machine running a combination frontend/backend machine with a bttv card. This system barely kept up with 480x480 nupplevideo for livetv. This proved the concept and got me hooked. I began scrapping together hardware and specing new hardware for a production system.
Production use in my home began around November of 2005. I took an old my desktop machine, an old 1.4GHz Celeron on a slot 1 motherboard, and turned it into a fulltime backend. I used two Avermedia M179 cards for this first system. The ivtv drivers were buggy, the image was snowy, and they were hot as ovens, but the system worked. I promptly decided on diskless frontends with gentoo-based root filesystems on the backend. The initial frontend an Athlon 2400+ mobile based system came up on the living room tv and I was the primary user. My wife started using it in the summer of 2006 and budget allocation was made to prepare for Fall premiers. The Avermedia's went out with the trash and 1 shiny new PVR-500 was purchased. That worked for about a week until we realized there were way too many conflicts with just 2 tuners during premiere time. A second PVR-500 was purchased and the death spiral of the Samsung tuner was found. Many ivtv upgrades and finally a patch and all was reasonably good with the Samsung card playing backup. It was then that we hit another impass. The backend could not keep up with the database, 4 recordings, playback, commflagging and serving out root filesystem to the frontend. Thus began the great backend split.
In August of 2006, the first backend was demoted to serving the root filesystem of the frontend, commflagging and transcoding. A $60 pentium III 933MHz machine was purchased that had a much newer motherboard. This got a 40GB boot drive and a massive 250GB tv storage drive. I NFS mounted a 120GB drive from my desktop with our photos and music on it and added a few movies. This became the gallery, music and video drive. The demoted backend served up the primary /myth directory from a 160GB drive. This was also the time of development of a second frontend for my then 3 year old daughter. This came online around January 2007 on a TV in our guest bedroom. Many happy days were had a my daughter watched endless commercial free children's shows and my wife and I finally got to watch sitcoms and other junk in the living room.
I'll take a second to explain filesystem architecture. With 5 systems, 3 backends and 2 frontends, NFS mounting drives a huge reboot issue developed. If a the system with the drives went down for reboot, sometimes NFS links would not come up in the right order and things got failed up. So to fix it I placed NFS mount points on each machine in the /mnt directory. Then the /myth directory is a series of symlinks to the /mnt directories. This seems to work very well. This system has been fine tuned several times since the initial incarnation.
Fast forward to August 2007. We have 2 fulltime network boot SD frontends that network boot from backend #2. The second frontend actually is connected using 2 OpenWRT flashed wireless routers using a WDS connection. This needs some fine tuning, but so far works pretty well. There is a third diskless frontend which is based on the ASUS Pundit A1-PH2. This is just awaiting my wiring up another IR detector and will become the primary frontend. The current primary frontend will be demoted to the bedroom. We are now at 1.03 TB of space on 3 separate machines. We have a 500GB drive in the primary backend for TV and a 250GB drive for movies. The secondary backend has a 160GB drive for the frontend root filesystems and extra movie storage. The final 120GB drive stores movies, music and photos and resides in my desktop machine.
October 2007, the secondary backend motherboard failed as my daughter says, "What happened to my movie Daddy!!!". Quickly, fearless Daddy hops on the newegg site and orders new goodies at Wife's screams to calm children. Meanwhile back at the lab Daddy is multitasking by digging through goody box and comes up with EPIA 5000 board. Replaces secondary backend with this board and a miracle happens, it boots and just works after forcing the right network driver to be loaded. And the new toys are still on there way, as they shipped before the miracle happened. The first rackmount low power athlon dual-core mythtv server should come online before the end of the year.
The fun thing is that all this hardware has been acquired slowly over time. The system is now taking on a life of its own. My primary focus has been on reliability. I hope to have some more redundancy at some point. I do backups of the database, but other than that I am at the mercy of drives for movies and tv. HD is also probably a few years down the road. Even on a 42" LCD, the SD signal through S-video still looks pretty good. No, I will not look at a real HD signal and ruin my blissful ignorance.
Recently, we removed our DVD player from the entertainment center in an effort to streamline the look. Mythtv became "the" DVD player. The glaring issue was that is the diskless boot server went down for any reason we now do not have a DVD player. This made WAF drop a bit. So now my plan is to actually boot from 4GB USB drives on the frontend machines. That way if all the backends die, DVDs will still play on the frontends, but the noise of the frontends, which are virtually silent, does not increase. This should also help in the future when I saturate the 100Mbit lines with HD.
November 2007, added new server as described above. I still need to iron out a few small issues with rebooting, but everything is working at least as good as it was before. Used Knoppmyth R5F27 to build this machine and then migrated a knoppmyth backup from the old machine to the new one. Storage groups is working like a charm. The machine is quieter, the processor fan has been mostly off with the top of the case off for setup. It's amazing how much heat 4 drives give off when they are working, luckily the case has a nice 4 inch fan right in front of them. I now need to repurpose the old 933MHz machine to replace the EPIA 5000. I also need to complete the build of 2 more frontends for a total of 5.
December 2007, two 500 GB drives for standard definition, SD, television seems to be enough for our 4 person household. That is until my 2 daughters get a little older. The new master backend machine is running like a champ and the 500 GB drives are seperate filesystems linked into myth by storage groups. Storage groups is working great with no issues so far. The 933 MHz machine is up as the slave backend and serving out the frontend filesystems very well. Transcoding is incredibly fast, with 3 backends running. The dual core processor in the master backend flies through transcoding, with 2 files transcoded simultaneously at close to 70 frames per second each.
I had some issues with mythvenus which is running over a wireless network. I have found that I have lots to learn about wireless networking. The fun part is that I have decided not to mess with wireless network adapter in linux. Since wireless routers are around $50 that is what I am using with a nice program called OpenWRT. I have a WDS connection from my upstairs router to the downstairs one. I'm only using WEP encryption, but I figure something is better than nothing. The link distance is only about 30 feet through 1 wall and I'm running a 802.11G network. The mythtv interface was generally responsive, but every so often the video would skip and sometimes it would begin skipping continuously. This is the only connection on these routers, so I know that should not be the issue. I bumped up the power output of the routers and things got a little better. So Last week I decided to try something different. I logged into the remote mythtv machine and sent a 2 GB video file from it to the server. This saturated the wireless link and I was able to see the throughput in the web interface of the remote router. The first thing I noticed was that the link was only running at about 7-10 Mbits/sec. The killer was that every so often, the bandwidth would drop to zero. I'm pretty sure this was what was causing the skipping. I then began changing wireless settings and watched the result. The first thing I played around with was the output power on the two routers. I noticed that increasing it really didn't help me any, so I left it at the default. What did seem to help is that my routers each have 2 antenna. I switched the sending to one antenna and the receiving to the other antenna on both routers. This immediately got rid of the zero bandwidth dropouts. The bandwidth still dropped, but never to zero. I still have more optimization to do, but for now my kids are happy with non-skipping TV and movies.
Well, my wireless adventure has gone downhill to nothing. The dropouts continued and only seemed to degrade. The sad part is the distance is only about 20 feet with one wall in between. The connection appears strong on both routers, but the transfer rate is abysmal. I even tried removing the WDS connection and just bridging, no dice.
February 2008, My wireless adventure is over. I yield to the invisible wireless gremlins that relentlessly tortured me. I spent a day this past weekend running another wire set to the kids playroom. The wiresets I have been running are two cat5e and one coax to each room in the house. I label each end of each wire before bundling the 3 together with electrical tape. Seems to work very well so far. I have a few tools now including a 25 feet long fish tape, 48 inch flexible drill bit and a 12 inch spade drill bit. I was also lucky that I replaced the lighting in the hallway ceiling, which I pulled the wire through, with recessed lighting a few years ago. Easy enough to pop out the fixtures and see the wire run. I still have about 6 holes in a closet to finish patching, but finally having my TV back is worth it. They now watch there movies and shows on the playroom TV. The random nature of the wireless working had left us watching alot of kids shows on the big TV. I need to run wiresets to the bedrooms and wiring the house will be complete, as far as I'm concerned. The next owner can pull cat6 or fiber or whatever the flavor is that month.
February 25 2008, I finally completed the homemade LIRC receiver circuit for my new frontend, mythhades. This Pundit P1-AH2 is really nice. I used a IR receiver from a Hauppauge card and created a nice plug in one card slot cover to plug it into. I'm running to our LCD TV with a DVI to HDMI cable. The picture is very nice with DVDs and a little cleaner with SD TV. This is the fastest frontend I have ever had and the menus definitely seem a little snappier. I noticed today that is defaulted to running an 800x600 display size, because I never told it any different in xorg.conf. I will update and see how a 720p should look. The old frontend mythjester will continue duty as the master bedroom myth machine. I also have another old machine to make another frontend. That would bring us to 3 backends and 5 frontends, which is actually kind of interesting/scary that the system has grown this much. One backend and one frontend is actually my desktop, which is the only combined frontend/backend machine in the system.
One pet peeve I have been having since getting a widescreen HDTV is the letterbox bars on widescreen movies. I have been looking into using a script called fsmplayer to correctly crop the movies during playback. It is still a work in progress.