<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
On 27/08/13 18:16, Gregory Malsack wrote:
<blockquote cite="mid:521CDEDC.4060008@coastalacq.com" type="cite">
<meta http-equiv="content-type" content="text/html;
charset=ISO-8859-1">
<div class="popular-article">
<div class="user-contributed">
<p class="summary">Hey All,<br>
<br>
Growing call center. Currently at about 200 call center
staff, running about 1000 calls per hour. Gearing up to
double that. Not too sure that a single server will support
that growth. So, I'm trying to come up with ways to scale
the system and still maintain a simplistic design. So I'd
like to bounce some ideas around.<br>
<br>
Currently I am running on a Dell 1950, dual quad core
2.33ghz xeons, with 16gb ram, and 2 tce400p cards. This
server is managing the full load of the company. We are
recording all calls, running ivr, queues, cdr, cel, and web
for reporting. I currently have another 1950 of the exact
same specifications as a cold spare.<br>
<br>
Here's where you can see drawings of my current connectivity
and an optional connectivity I'm contemplating...<br>
<br>
<a moz-do-not-send="true" target="blank"
href="http://www.linkedin.com/redirect?url=http%3A%2F%2Fwww%2Epaydaysupportcenter%2Ecom%2Fcurrent%2Epdf&urlhash=qLsB&_t=tracking_anet"
rel="nofollow"><font color="red"><b>MailScanner has
detected a possible fraud attempt from
"www.linkedin.com" claiming to be</b></font>
http://www.paydaysupportcenter.com/current.pdf</a><a
moz-do-not-send="true" target="blank"
href="http://www.linkedin.com/redirect?url=http%3A%2F%2Fwww%2Epaydaysupportcenter%2Ecom%2Foption%2Epdf&urlhash=CJG1&_t=tracking_anet"
rel="nofollow"><font color="red"><b>MailScanner has
detected a possible fraud attempt from
"www.linkedin.com" claiming to be</b></font>
http://www.paydaysupportcenter.com/option.pdf</a><br>
<br>
As you can see I currently have a separate sql server and a
separate storage server for the call recordings. This is all
working fine.<br>
<br>
However, I'm thinking for scalability I should be looking to
migrate to a configuration similar to the one in option.pdf.
Where I have a VOIP gateway server that simply relays
traffic and possibly can do some load balancing or
intellegent routing. But nothing more then that, and
possibly a second one of these online as a hot failover.<br>
<br>
Then have separate sql, storage, (i forgot it in the pic)
web, and asterisk servers behind that on separate dedicated
network. Here's my dilemma though, how do I balance the load
across multiple machines for scalability...<br>
<br>
Since 95% of our calls come into queues, I need to be able
to maintain queue stats and presence across all of the
servers. Thus far, I've got everything except the
extensions.conf file into the mysql database. I thought
about setting up 2 servers, 1 for sales, and 1 for customer
service, then possibly break out each call queue to it's own
server as things grow. Just not sure if that's the right way
to go.<br>
<br>
Then regarding extensions.conf, I've read that it too can be
placed in the sql database and accessed via switch. however
it's resource intense, so now I'm thinking of maybe putting
that file on the nfs server for all of the boxes to read
from.<br>
<br>
As for the design of that file, I was kind of thinking of a
modular design within the file using various goto's and
gosubs. Our business model is based on affiliates and
corporate marketing, so we have a ton of did's that follow
the same call flow with minor modifications in some
variables, as well as variations in call flow, and hours of
operation. Thus the modular design of the call flow. Then
the primary inbound context would simply be a list of did's
pointing to a goto with a list of the variations and
variables for the did.<br>
<br>
Ok, now that I've melted your brains.... thoughts?<br>
<br>
Thanks all in advance for the discussion...<br>
Greg</p>
</div>
</div>
</blockquote>
<br>
We have a similar server but a single quad core at 3Ghz. It easily
handles 400 concurrent calls with a lot shorter average call
duration than you have. It doesnt do as much call recording but does
do a lot of AGI stuff.<br>
<br>
With regard to nfs thats fine for non real time stuff. Personally we
have a test machine and multiple live machines and use subversion to
commit any approved changes and then check them out on the live
boxes. We dont need to worry about shared file space and we get
version control of the configuration as an additional benefit.<br>
Its similar for call recordings. We have call recordings going to a
ram disc and then when they are complete there is a background
process to copy them to the nfs volume. If nfs is unavailable then
they are moved to the internal disk temporarily until the nfs is
back online. We have never used this functionality but it add a
little redundancy.<br>
<br>
I would put opensips at the front end which looks at the incoming
destination number and routes the call to the appropiate front end
asterisk box depending on the queue it should go to. The other
asterisk box(s) will be a backup so if one asterisk box fails then
one of the others takes over running that queue automatically.<br>
<br>
For call recording are you using mixmonitor?<br>
I would consider using the normal monitor command and pass these
recordings off to the nfs and have another machine process them by
mixing both legs and perhaps converting to mp3 aswell.<br>
<br>
</body>
</html>