ndchost have a procedure on their kb for installing trixbox on a centos vps, i have used this several times and it works well the article is here
I can confirm this works well. I actually installed a Trixbox 2 VE right alongside my other Asterisk/Free PBX VE mentioned in my other post and they both work great. I prefer the compile from source I did with Asterisk and FreePBX over the Trixbox 2 because I can add all the bells and whistles that the current Trixbox runs plus more. However, Trixbox 2 will certainly get you up and running.
I should note that both my VEs are running on OpenVZ and the MeetMe conferencing application works very well. In fact, I have managed to get all Asterisk addons to work with no timing problems after properly installing ztdummy and configuring the VEs appropriately. My phone calls are crystal clear and overall I am extremely happy with running Asterisk on a VPS system.
I chose a VPS because I simply enjoy working in different server environments and don't have the funds to lease 5 different servers to do 5 different things. On a VPS I can tinker under the hood of 5 different environments with one nice server and allocate my resources accordingly.
Finally, OpenVZ works very well with Asterisk, however I did encounter a fair amount of network issues at first until I could successfully wrap my head around the Virtual Ideology of OpenVZ. That was probably the hardest part for me.
Overall I was able to get most networking issues resolved quite easily with OpenVZ and Asterisk. This is probably because I understood pretty well what OpenVZ was doing and how Asterisk was supposed to be setup. With that said I did have some issues when installing and working with Bind, APF, and IPtables. I know a fair amount about APF and BIND, but needed to understand better how they worked in a VE. Webmin helped me to visualize things a bit better after I installed that. With regards to IPtables I did not have much experience with this so I bought a book and studied for a couple of days to get the basics. From there I was able to troubleshoot better.
Probably the biggest problem I had was regarding my Firebox Watchguard. I had to configure that to communicate with my Aastra 57i CT and Remote Asterisk Server. I was getting a lot of REACHABLE and UNREACHABLE issues in the Asterisk log. This initially had me going through DNS, IPTables, and APF on both the HN and VE which ultimately lead to the Firebox. There was confusion in the air and once I setup a dedicated port or route, all of my problems totally disappeared. For the past week or so I have had zero issues. Works much better than my Skype setup at this time. The Aastra XML features are awesome and love pulling RSS feeds with a push of a button.
Asterisk runs very well on an OpenVZ vps with my experience thus far. I'm quite impressed. However, it should be noted that I am not running a hosting business. I am simply running my own (other) business with the server and using several DIDs I've purchased through Vitelity. What I like about the VPS is that I can create new VEs to experiment with other operating systems, PBX solutions, or whatever without having to dedicate the entire box. My friends, family, and business contacts have been ringing me all week and I haven't missed a call. Not only that but all the goodies you can setup over at NerdVittles work very well since I am on a source compiled system which if correct more closely resembles PBX in a Flash rather than Trixbox.
The XML on the Aastra allows me to connect to SugarCRM to access my contacts list. AsteriDex works well too. XML is just awesome because I can access so much without even having my computer on.
Using a VPS simply has allowed me to maximize the return on my investment each month by purchasing a remote server. I can't imagine using a dedicated box for this at home simply because I use too many applications in my job and don't want any interference, not to mention I don't run my computers 24/7. I wish more Asterisk solutions like Trixbox, PBX in a Flash, the new Druid and other would offer an alternative to ISOs for those of us who wish to tinker with Remote systems. This is the only area that I can't figure out why hasn't become more popular. For me it has been remote or nothing so compiling everything from source or using the Trixbox 2.0 version are the only solutions. Perhaps I am incorrect?