After watching this a while I feel that I must weigh in based on my own experience. I've taken an embedded system approach to my Asterisk installation from a time when this was not at all commonplace. My earliest embedded systems were early in 2004.
AFAIK Astlinux was the very first distro to be carefully tuned for booting and running from flash media. In a small office environment I can say with certainty that my very first system would still be running today if I didn't take it down. And THAT was running using a small, cheap Dane-Elec CF card recycled from an old digital camera. Once that system was down I wrote a script to drive that CF card into failure, just to see what it would take. I been using the old (0.43) Astlinux release and a CF card with three partitions since that reelase came out with no problems at all. Clearly, I'm not running a call center. But I do work from home full-time. The system handled all my work and home calls until very recently. Much effort went into Astlinux to ensure that flash wearing was addressed. All of my experience points to this being a theoretical problem more than a practical problem. Until someone can point to systems actually failing I think that the developers are not only to be believed, but commended. In reviewing the Jazinga Asterisk appliance recently I was pondering their used of an Intel SSD over a cheaper flash module. Then when their CTO was later on a Voip Users Conference call and they got to speaking with Darrick it became clear that Astlinux likely has a better architecture for dealing with flash memory that their product. They were interested in learning about the dev enironment and various techniques employed in Astlinux. Truly, Astlinux is in a leadership position WRT embedded Asterisk on small format hardware. Michael Graves References cited: http://www.smallnetbuilder.com/content/view/30660/80/ http://www.voipusersconference.org/ On Fri, 02 Jan 2009 13:40:06 -0500, Philip Mullis wrote: >Despite the prior comments; CF's can quickly degrade as there is more to >writes than just files, most people dont even take into account that the >os will actually do writes every time a file is accessed to update its >last access time, options in your fstab such as noatime and nodirtime >can extend the life greatly on your cf. > >In terms of what you can and cannot move will vary based on what you >install.apps on your base image. >You can use things like iostat to verify the amounts of writes that have >been done to various mounts. > >Most things like logs can be moved without worry to a memory disk. >(although keep in mind you will loose them on power cycle) > >A good methodology for taking care of the writes is to create a memory >disk ie (/tempdisk) and symlink any directory/files back to it which are >written on a regular basis (such as logs) or temporary files. > >You have to watch out though that your memory disk is properly sized for >your system or you could run into errors when its full. A good way to >deal with growing log files is something like clogd which lets you do >circular log files with a specified max size. (this is the bsdports, but >you can probably dig out the code and compile it for linux) > >Regards, > >Philip Mullis. > > > >Martin Rogers wrote: >> David >> >> some nice questions. Answers from those in the know please. >> >> Mart >> >> >> >> David Kerr wrote: >> >>> The asterisk-gui writes into its source directory >>> (/var/lib/asterisk/static-http/config) a fair amount to grab the output from >>> system commands that it executes. There is no reason why this has to get >>> mirrored onto the flash by unionfs. I could probably figure out how to >>> modify the asterisk-gui to write to some temp directory (that would be >>> ramdisk only, and not unionfs). Does astlinux have such a place? >>> Also, syslog files are another source of constant flash writes (asterisk, >>> dhcpd, others are always writing). Can this be moved to a ramdisk that is >>> not unionfs? >>> >>> What else (other than voicemail and CDR) is updated to flash on a regular >>> basis? >>> >>> Thanks >>> David >>> >>> On Wed, Dec 31, 2008 at 1:22 PM, Darrick Hartman >>> <dhart...@djhsolutions.com>wrote: >>> >>> >>>> <20081230234655.b25dae38...@lizzy.djhsolutions.com> < >>>> 495abb45.80...@mhr.me.uk> >>>> Message-ID: <1700fa0442cb0b87f7e6a60437e79...@localhost> >>>> X-Sender: dhart...@djhsolutions.com >>>> Received: from 68-191-180-6.static.fdul.wi.charter.com [68.191.180.6] with >>>> HTTP/1.1 (POST); Wed, 31 Dec 2008 12:22:25 -0600 >>>> User-Agent: RoundCube Webmail/0.1 >>>> Content-Type: text/plain; charset="UTF-8" >>>> Content-Transfer-Encoding: 8bit >>>> >>>> >>>>>> On Tue, 30 Dec 2008 22:47:27 +0000, Martin Rogers >>>>>> <fromastlinux-us...@mhr.me.uk> wrote: >>>>>> >>>>>>> Michael Keuter wrote: >>>>>>> >>>>>>>>> Michael Keuter wrote: >>>>>>>>> >>>>>>>>>>> Since upgrading to 0.6.2, partitioning my flash disk and running >>>>>>>>>>> genunion I am now not only able to make ordinary configuration >>>>>>>>>>> >>>>>>> changes >>>>>>> >>>>>>>>>>> sticky but the root password too. >>>>>>>>>>> >>>>>>>>>>> The trouble is however that if your mobo only supports a single >>>>>>>>>>> >>>>> hard >>>>> >>>>>>>>>>> disk channel, having multiple partitions does not really help. If >>>>>>>>>>> >>>>>>> the rw >>>>>>> >>>>>>>>>>> partition wears out it might as well all be on the same partition >>>>>>>>>>> >>>>>>>>> >> anyway, as the whole flash module will need changing. >>>>>>>>> > >>>>>>>>> > You have still the possiblity to use an extra USB-Stick for the >>>>>>>>> > Keydisk (genkd script). >>>>>>>>> I was not aware that it was possible to make the root password sticky >>>>>>>>> using genkd, perhaps I missed something. I understood this needed >>>>>>>>> genunion. Genunion on a USB-stick was a non starter for me - the >>>>>>>>> USB-stick could not be detected at boot-up. Possibly a timing issue. >>>>>>>>> >>>>>>>> No that's the wrong way. Before running genunion >>>>>>>> run genkd /dev/sdÅ (your USB-Stick). >>>>>>>> Check with "fdisk -l". Reboot then. >>>>>>>> Now run genunion and at the second question say "NO". Reboot again. >>>>>>>> >>>>>>>> http://www.astlinux.org/node/30 >>>>>>>> >>>>>>>> >>>>>>> Michael, thanks for your post. I did try the above, on more than one >>>>>>> occasion and with two different platforms, but after booting no >>>>>>> configuration was sticky. I had an error on bootup to do with detecting >>>>>>> the USB Stick. This was using the 0.6.1 VIA image. >>>>>>> >>>>>>> I then reverted to using a second on-board partition and got everything >>>>>>> working nicely, except for concerns about extending the life of the >>>>>>> >>>>> disk. >>>>> >>>>>> Honestly, I think this is all blown out of proportion. Recent flash has >>>>>> good built in wear leveling. Assuming you use a large enough disk, even >>>>>> >>>>> if >>>>> >>>>>> you did have problems where portions of the disk were no longer >>>>>> >>>>> writable, >>>>> >>>>>> the only affect should be the amount of free space on the device. The >>>>>> amount of data that's written to the CF is fairly small. If you're >>>>>> >>>>> super >>>>> >>>>>> paranoid, use a 4GB card and swap it out proactively in a few years. >>>>>> >>>>> If you consider this as being commercially viable then we are looking at >>>>> different business models. >>>>> >>>>> Mart >>>>> >>>> Given your options, the compact flash card is going to be more reliable >>>> than a usb stick. That's the point I was trying to make. The actual >>>> 'life' of a CF card or any other storage device is dependent on several use >>>> (user) factors. With the steps we've taken, there are minimal writes by >>>> default to the CF. >>>> >>>> AstLinux is intended to be a tool that you can use however you want to >>>> (within reason). If you don't want to store voicemails on a CF card, feel >>>> free to store them elsewhere. If you feel that a hard drive is going to be >>>> more reliable, then by all means, install it on a hard drive. >>>> >>>> Regards, >>>> >>>> Darrick >>>> >>>> >>>> >>>> >>>> ------------------------------------------------------------------------------ >>>> >>>> _______________________________________________ >>>> Astlinux-users mailing list >>>> Astlinux-users@lists.sourceforge.net >>>> https://lists.sourceforge.net/lists/listinfo/astlinux-users >>>> >>>> Donations to support AstLinux are graciously accepted via PayPal to >>>> pay...@krisk.org. >>>> >>>> >>> ------------------------------------------------------------------------ >>> >>> ------------------------------------------------------------------------------ >>> >>> >>> ------------------------------------------------------------------------ >>> >>> _______________________________________________ >>> Astlinux-users mailing list >>> Astlinux-users@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/astlinux-users >>> >>> Donations to support AstLinux are graciously accepted via PayPal to >>> pay...@krisk.org. >>> >> >> ------------------------------------------------------------------------------ >> _______________________________________________ >> Astlinux-users mailing list >> Astlinux-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/astlinux-users >> >> Donations to support AstLinux are graciously accepted via PayPal to >> pay...@krisk.org. >> > > >------------------------------------------------------------------------------ >_______________________________________________ >Astlinux-users mailing list >Astlinux-users@lists.sourceforge.net >https://lists.sourceforge.net/lists/listinfo/astlinux-users > >Donations to support AstLinux are graciously accepted via PayPal to >pay...@krisk.org. > -- Michael Graves mgraves<at>mstvp.com http://blog.mgraves.org o713-861-4005 c713-201-1262 sip:mgra...@mstvp.onsip.com skype mjgraves fwd 54245 ------------------------------------------------------------------------------ _______________________________________________ Astlinux-users mailing list Astlinux-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/astlinux-users Donations to support AstLinux are graciously accepted via PayPal to pay...@krisk.org.
