Help with System Specs for call recording

I currently have an asterisk system running 8 analog lines (two digium cards) which are continously busy throughout the day; approx. 2500 calls/day.

The system is using music on hold, call queuing and records every call. Codec is G.711.

The issue is that after 5 months of operation, the voice starts to cut in-and-out and the voice quality is low. Plus the asterisk machine is running at 100% CPU load and the hardrive I/O light is basically solid.

The Machine is as follows:
P4 2.4 GHz
512 MB RAM
5400 RPM IDE Hardrive (840GB)

Okay here is my question:
I understand that my system specs are quite low for what I am trying to accomplish, and I am sure that the hardrive is basically worn out; in fact I have replaced it once before.

What I want to know is what type of system should I have running if I want to record every call, whether I expand from 8 to 50 simultaneous calls?

Will there always be a problem with the disk continously reading and writing even if I use SCSI disks?

Thank you for any advice in advance.

  • Gulzar

are you using mpg123 or Asterisk-native for MoH ? how much swap space is being used ? any IRQ conflicts/sharing ? what else is the machine running ? any GUI/X ?

scsi all the way dude :smile: get a nice scsi raid card with atleast 128MB memory. do raid 5, but if your recording files are large (over 50MB a piece) you should modify your stripe size on your array, and make it a tad larger than stock.

Scsi will give you tons less overhead, and IRQ issues compared to IDE.

Also you should really have dual CPU IMO if your running two PCI line cards - then you can place each card on a different CPU, this should help a little.

100% cpu is bad news, and could be a multitude of things. Also any transcoding will just destroy your preformance!

you might also consider using a RAM disk for call recordings:

towards the bottom, there are two links, i would suggest reading up on them…recording lots of calls straight to disk can really bog your system down.

alternately, you might consider recording to a network storage share/device instead of the local disks, run dual NIC’s and just route all your VOIP traffic over one while all other data is routed over the other…

just a few thoughts.

Yeah RAM disk isnt a bad idea…

My concern with using a NIC / network storage is the amount of interrupts that can cause - I notice very few interrupts on my SCSI raid card compared to the NIC.

The network card on my system is nearly 40x the interrupts. and my IDE (only used for the CDrom, not really used is 8x the scsi card…)

With my experience the less interrupts the better.

true, but with a dual proc or dual core machine, you can tie the NICs to differnet CPUs, and with some work, you can effectively tie asterisk to it’s own CPU, and let the rest of the system work on the other. if you have a dual-core dual-proc system, it gets even better…

also, if you’re not running a digium card, you don’t really have to worry about interrupts.

not saying this is the ideal solution, but i think it’s the path our company is heading, as we can have centralized storage/config servers that are made extremely redundant, while the actual asterisk servers act as nothing more than high end storageless processing units - eventually i want to have the systems run entirely off a RAM disk, ala astlinux - no hard drives to worry about, almost zero latency, etc…

just thinking out loud.

yeah totally - I see that as a great solution.

Im stuck using a PRI for the time and in interrupt hell if im not carefull, but when we move to VOIP (internet) then this is something I am going to look at as well - I LOVE ramdisk/CF setups, they work great, and have like no moving parts :smile:

yeah, we’re also stuck with four PRI’s per box…the only good news is that we have both digium and sangoma hardware, and the sangoma’s seem to work much better in regards to IRQ sharing.

even if they don’t, i’ll just move the sangoma’s to one CPU, and everything else to the other - considering we’re not really loading our boxes up that much, it should work out fine…

if you absolutely cannot get your hardware to work, you might take a look at a sangoma card - they’re about the same price as the digium stuff, and we’ve been largely happy with them, except for some inband DTMF issues with the echo canceller on…