[asterisk-users] I need a second opinion on a new phone system deployment

[Nunya Biznatch]

Howdy All,
    They say opinions are like belly buttons, everybody has one. (that's 
the "clean" version of the saying). So I'm asking for yours. I hope you 
see it as a fun exercise.

I'm designing a phone system from the ground up. Will be about 1000-1300 
seats mixed 80/20 VoIP/Analog. 58-acre campus environment with 23 
buildings. Userbase is emergency services organization, 24/7/365 
operation. Down time is not an option, but "blips" are acceptable. 
Repair time is immediate. We need failover for the failover essentially. 
However, money is a major factor, so I have to do it all for nothing. So 
here's what I'm thinking. Please throw in your 2 cents.

Network will be separate for phones. Fiber infrastructure available 
between buildings as well as copper. Internet access will be limited to 
a single administrative console on a temporary basis, and then only when 
remote 3rd party support is required. Access for 3rd party support will 
be supervised through remote access tools such as VNC, GoToMeeting, 
etc... etc... System will have zero access to local data network. This 
means all ancillary support servers such as DHCP, DNS, NTP, FTP, 
etc...etc... will be specific to the phone system. Yes, I know some 
responders at this time will become fixated on me gaining this 
connectivity. It ain't gonna happen. It's not an option. Period, end of 
story. These are the parameters I must work within. Trying to "fix" that 
will be a non-starter.

The phone system will upgrade an existing TDM-based system. Mitel SX2000 
with NuPoint Voicemail. This will not be a dump-trunk replacement. I 
expect at least a one to two-year transition, meaning we will have time 
to find problems,  work bugs, and learn over time, with minimized 
impacts. It also means we'll be supporting two systems for some time.

PBX is 97% serving your basic phone on the desk. Nothing special. 
Customers expect the usual list of features. There will be a goodly 
number of hints required for BLF on maybe 150 phones. There is one 
office of about 30 phones in a call-center environment that will need 
that service. They would be considered low volume (but don't tell them 
that).

My Skills... I am not a Linux kung fu master, but I have built and 
managed my share of Linux servers on mutiple Linux flavors. I am a DCAA, 
having been through formal training, and have been playing with Asterisk 
for years, but always in fits and spurts and never in a live environment 
so I am by no means a kung fu master there either. I have started 
dabbling with virtualizations via XEN, but I am not comfortable enough 
with it to go live this first round. I can see myself implementing it in 
about three years once we're totally comfortable with what we have, so I 
can then have time to get that skill sorted. I was a network engineer 
for the US no3. telecom for a number of years, 10-years in 
comm-electronics in the military before that. Telecom my entire career. 
I've got the kung-fu to handle the network side of the house, and having 
administrated multiple PBXs for decade-plus, I've got the concepts down.

No plans to build databases for things like directories, etc... I'm not 
greatly confident in those skills, and to date, haven't found anything 
that really stands out that would make me require that. You may think 
otherwise, so please chime in. I say that, but at the same time I 
recognize I may require a GUI interface once fully deployed to allow 
lower-skilled people to follow the motions to complete simple moves, 
adds, and changes. I'm fighting the uphill battle that is the "GUI is 
new, CLI is old" mentality.

System will use G.722 for VoIP Phones.

So there's the groundwork. Here's the hardware plan.

Plan is to build my own servers following industry standards (ATX) and 
using industry standard equipment. Why? Spares? Whether redundant or 
not, I will still have spares for the most common elements on the shelf 
so equipment can be returned to service as quickly as possible. This 
will also allow me to be comfortable with more "basic server" 
configurations and help keep cost down. For example, Servers with single 
power supplies vs. dual. Also, components will be standardized for all 
equipment to aid in supply requirements.

First the layout.

2-servers acting as gateways. Each handling 2 PRIs for outside trunks. 
They'll also handle the analog ports. Failover will be in the form of 
degraded trunk access if one should fail, but the second will be able to 
support services in degraded fashion.

2-servers acting as VoIP PBX. A primary and a spare. Meaning one will be 
capable of handling the load of the entire system, and the other will 
pickup when the other dies, an active/passive cluster. Will also take 
care of voicemail. Use of heartbeat, pacemaker, etc... etc...

2-servers for support services. DNS, DHCP, FTP, NTP, etc... 
etc...Basically, everything the phones need to run plus system 
monitoring via something like Nagios.

1-Desktop for administration of everything. Provided from corporate. 
Basic Desktop.

Looking at Intel Xeon E3-1230 ivy-bridge processors. 8GB DDR 1333 for 
Gateways and 16GB for PBX and support servers. 1TB drives in RAID 10 via 
LSI 3ware 9650 cards for PBX, 250GB for Gateways. Supermicro X9SCM-F mobo.

OS of choice is Debian. Primarily because it appears to have the best 
availability for non-Internet installations.


Now the Infrastructure


2-network switches in the phone room. Each set of "primary" servers to 
one, and "secondary" servers to the other, and each switch connected to 
the other. Each switch will have a different path to the network. RTSP 
implemented for dual path to the campus. Only one location on campus 
will have or require dual paths to the network.

Most buildings on campus have cat-3 for voice installed in the mid-90s. 
Wired at the same time as the data network, I can generally conclude 
they're the same length. It's terminated to 110-blocks on walls. Some 
cabling is only 2-pair. I know I will find surprises. Essentially, I 
plan to re-use this cable, knowing in some circumstances I will need to 
make special patch cables. These connections will be forced to 10BaseT 
at the switch.

I require PoE to the wire closets, no power sourced at the desktop. I 
require a minimum eight-hours emergency power which will be in the form 
of UPS in most cases. Why so much backup? Well if you ask, we can start 
a new discussion about NEBS compliance, E911 Federal, local, and state 
requirements, etc... etc...

So why not use existing data network? The current data network consists 
primarily of 10+ year-old 100BaseT switches, no PoE. Barely any backup 
power. I don't believe they're using QoS. The network office is a 
separate department from the phone office. I question their skills, and 
above all, network folks treat phones like computers, not like 
multi-million dollar lawsuits when they don't work in an emergency. We 
could make another thread out of this huh? To use existing data network 
would require hundreds of thousands in Cisco 6500 and 4500 series 
switches. Network has already stated they'd want phone on separate ports 
from computer, and I agree. (Yet another thread). Thousands of computers 
across 23 buildings, and it must be Cisco by corporate policy, where 
phone is a different animal that doesn't have this limitation. You can 
see we're talking hundreds of thousands in just switching gear. Then UPS 
requirements to support a big hog of a switch vs a teeny 48-porter 
w/PoE, and you just cranked up one-time and long term cost for that as 
well. Trying to replace the network to support the phones is cost 
prohibitive and a non-starter. Maybe we can talk about it in 5 years 
once they've replaced everything.

I plan to purchase lower-cost Layer-2 smart switches from vendors such 
as DLink, Xyxel, Dell, etc... Many players in the market for 48-port 
switches with PoE and multiple SFP.

I think that's probably enough... I apologize for the large email but I 
couldn't think of a better way to get a qualified peer opinion without 
laying out the facts.

Thanks in advance for your review and consideration...!!!