telefaks*de Virtualisierung einer OpenSource Telefonanlage mit Freeswitch und Proxmox/OpenVZ Peter Steinbach Telefaks Services GmbH

Transcription

1 P telefaks*de Virtualisierung einer OpenSource Telefonanlage mit Freeswitch und Proxmox/OpenVZ Peter Steinbach Telefaks Services GmbH Tel.:

2 P Abstract Existing OpenSource VoIP-Solutions Asterisk overview Freeswitch overview Types of virtualization Virtualization of Asterisk Virtualization of Freeswitch Proxmox / OpenVZ Pitfalls you may run into Some screenshots /videos of a PBX based on Freeswitch

3 Existing common OpenSource VoIP-Solutions Asterisk Freeswitch Kamailio / OpenSIPS / SER SIPfoundry SipX Yate

4 Existing OpenSource VoIP- Solutions Asterisk (1) originally created in 1999 by Mark Spencer of Digium Operating Systems: Linux NetBSD, OpenBSD, FreeBSD Mac OS X Solaris AsteriskWin32 Features PBX Voice mail Conferencing IVRs automatic call distribution (ACD) Recordings Call volume Up to 200 concurrent calls / machine

5 Existing OpenSource VoIP- Solutions Asterisk (2) Protocols SIP ISDN (S0/E1/T1) Analogue lines IAX2 MGCP H.323 SS7 Interfaces Variety of GUIs, from easy to complex, Example: Elastix (1 Mio downloads lately) Programming Interfaces AGI AMI Current version (January 2011)

6 Existing OpenSource VoIP- Solutions Freeswitch (1) originally created in 2005 by Anthony Minessale and other previous Asterisk developers Call volume Up to 5000 concurrent calls / machine Up to 50 call setups / sec Features VoIP Switch PBX Transcoding B2BUA IVR & Announcement Server Conference Server Voic Server SBC (Session Border Controller) Fax server T.30/T.38 and gateway ENUM

7 Existing OpenSource VoIP- Solutions Freeswitch (2) Operating Systems: Linux FreeBSD Mac OS X Solaris Windows Protocols SIP ISDN (S0/E1/T1) Analogue lines SCCP H.323 Jingle / Google Talk / Telepathy Programming Interfaces XML-Curl XML-RPC Socket ODBC

8 Existing OpenSource VoIP- Solutions Freeswitch (3) Programming languages JavaScript Ruby Python Perl Lua.Net Enryption TLS SRTP ZRTP Current version (April 2010)

9 Existing OpenSource VoIP- Solutions Freeswitch (4) Our Goal: Deploy Freeswitch communication servers (similar to well-known Asterisk/Elastix on CD) More stable and realiable Entry levels Basic system, OpenSource Small business edition with enhanced fatures (Encryption, Fax-Server) Enterprise edition with professional support (Encryption, Fax-Server, Operator Panel, Cluster)

10 Types of virtualization (1) Virtualization via OS-Container Characteristics OS and kernel is shared ( kernel virtualization ) Hardware is shared e.g. no Windows inside Linux Benefits Performance Low memory usage Drawbacks Only OS with same kernel can be virtualized Sometimnes difficult to handle hardware resources Examples OpenVZ / Proxmox Virtuozzo Linux-VServer User Mode Linux

11 Types of virtualization (2) Virtual Machine Monitor (Hypervisor) Characteristics Sharing of hardware No sharing of OS and Kernel, e.g. Windows can run virtualized inside Linux Benefits flexible Drawbacks Performance loss Examples Parallels Desktop and Parallels Workstation VMware Workstation, VMware Server Microsoft Virtual PC VirtualBox KVM

12 Types of virtualization (3) Hardware virtualization Characteristics Like Virtual Machine Monitor, but also virtualization of hardware e.g. Windows can run inside Linux Benefits Very flexible can e.g. run old OS on new hardware Drawbacks Performance loss Examples VMware Workstation, VMware Server Microsoft Virtual PC on x86 KVM Xen 3.0

13 Types of virtualization (4) Hardware-Emulation Characteristics Emulation of Hardware (e.g. different CPU) e.g. Windows can run inside Linux Benefits Very flexible, can emulate as a matter of principle any machine on the target system Drawbacks Severe performance loss Examples Bochs QEMU PPC-Version von Microsoft Virtual PC Game console emulation (Nintendo, Playstation)

14 Types of virtualization (5) Paravirtualization Characteristics Sharing of hardware, but hardware is virtualized for performance OS needs to be adapted to virtualized hardware e.g. Windows can run virtualized inside Linux Benefits Flexible Only slight performance loss Drawbacks OS needs to be adapted to virtualized hardware Examples Xen 3.0 KVM

15 Which virtualization to choose? Asterisk and Freeswitch run realtime processes High system load on high call volumes Delays due to Virtualization deteriorates call quality (jitter and dropouts) 2 ways to go Virtualization via OS container ( kernel virtualization ) => maximum performance Paravirtualization => more independent of physical hardware and OS

16 Virtualization of Asterisk Started with Asterisk on VServer ( kernel virtualization ) Up to 100 conference members on 1 VServer, with max. fintuning (hardware, kernel, applications) Then migrated to OpenVZ, better finetuning of resources Tricky realtime clock issues, sharing of time synchronisation hardware across machines (e.g. Sangoma, Digium) Vicidial OpenSource callcenter suite successfully virtualized (up to 15 agents with recording on 4Core hardware) Larger installations require more machines We use Proxmox to easily deploy communication servers across several machines in our datacenters

17 Virtualization of Freeswitch No timing issues compared to Asterisk, even under high load No adaptations to the system needed (e.g. kernel) No signifcant performance loss compared to physical machine We chose kernel virtualization via OpenVZ (Proxmox) Why? Maximum performance Low resource usage (harddisk, memory) Thus processes can be seperated and unitized. Examples: 1 virtual machine for Freeswitch 1 virtual machine for SIP load balancer if needed 1 virtual machine for SQL server if needed 1 virtual machine for DNS server if needed 1 virtual machine for LDAP server if needed 1 virtual machine for VPN / Terminal server if needed 1 virtual machine for Firewall if needed Shifting machines and backup is integrated and very easy

18 Proxmox Screenshot Remark: 5 Phone systems are running on these 2 machines

19 Why specifically Proxmox? Best of 2 worlds with 1 machine Kernel virtualization (OpenVZ) Virtual Machine Monitor + Paravirtualization via KVM (e.g. for BSD firwall (pfsense) or Windows) Easy installation (Debian CD, 3 minutes) Manageable via Web GUI Cluster of multiple machines Live migration between cluster members Backup/Snapshot functionalities Heartbeat clusters work incl. DRBD OpenSource Active community Commercial support available (Vienna)

20 Pitfalls you may run into Proxmox does not do it all in complex scenarios Hardware resources and drivers have to be defined on the physical machine and need to be assigned to the virtual machine by hand Mounting external volumes can be tricky OpenVPN does not restart smoothly (needs VM restart) TimeZone in VM is usually wrong and need to be adjusted Normally no real MAC address in VM Not all applications compile on OpenVZ

21 Some screenshots of a PBX based on Freeswitch

22 Operator Panel

23 Map views Shows phone status in a Floor plan Building map Facilities plan Plant plan Initiate and transfer calls via drag & drop Combine with extensions from operator panel

24 Setting up IVRs and callcenter workflows

25 Outlook Freeswitch is the future Without Asterisk, Freeswitch would not be there Proxmox and OpenVZ is the best solution approach for virtualization of small Asterisk and large Freeswitch installations Freeswitch does not need any kernel modifications in a Proxmox/OpenVZ environment and thus is easier to handle Images of virtualized guest machines can easily be shifted across machines For high performance and high available VoIP projects, Freeswitch and Proxmox is the way to go.

26 Video Operator Panel Plot: We have some missed calls Drag 200 to missed call 203 When 200 and 203 are connected Drag 203 to parking lot Then we start a conference Drag 208 to conference Drag parked 203 to conference External call coming in 200 takes external call Drag 200 (external call) to conference Drag 200 to conference Delete conference

27 Video Operator Panel (map view) Plot: We add phone 208 to a room on the floor plan We call this phone by dragging 200 to 208 Watch how the colors of the phones change! Can be combined with Operator Panel

28 Thank you Peter Steinbach Martin Kudlek