- 1 General
- 2 Performance
- 3 Setup
- 4 Statistics
LVS stands for Linux Virtual Server, which is a highly scalable and highly available server built on a cluster of real servers, with the load balancer running on the Linux operating system. Users interact as if it were a single virtual server.
Is LVS software free?
Yes! All LVS software is released under the GNU General Public License (GPL).
Is there a FreeBSD port of LVS software?
Does LVS cluster support Linux servers only?
No, real servers can almost run any operating systems in a LVS cluster, such as Linux, BSDs, Solaris, and Windows. LVS/NAT balances servers of the operating systems having TCP/IP support, LVS/TUN requires servers having IP Tunneling protocol, and LVS/DR requires servers having a non-arp device. Almost all the modern operating systems support non-arp device.
How is the concurrent processing performance of current LVS software?
The ultimate performance of LVS depends on hardware that LVS runs on. An ordinary box with a single Pentium III processor and 100Mbps NIC card running LVS/DR can handle about 10,000 connections per second for web service. We have heard that a powerful box with good hardware and kernel tuning achieved 50,000 connections per second.
Can LVS handle more than 1 million simultaneous connections?
Yes, LVS can handle much more than 1 million simultaneous connections. One connection just costs 128 bytes in the LVS box, so an LVS box with 1G memory can handle more than 8 million simultaneous connections.
How do I check to see if my kernel has IPVS enabled?
How do i get counters from ipvsadm in order to create graphs from?
The current kernel 2.6 version of ipvsadm (v1.24) supports
ipvsadm --list --stats --numeric --exact
which gives you non-human-readable counters for Connections, Packets and Bytes for each Service Address and Realserver.
Install RRDtool and preferabely Cacti onto a host of your choice. From your favorite Linux distribution, install the Net-SNMP daemon onto the Loadbalancer host. Apply the Net-SNMP-LVS-Module to the Net-SNMP daemon. Using RRDtool and/or cacti you may query the Loadbalancer and create all kind of graphs using the statistics the Loadbalancers IPVS-module delivers.