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Try to run "modprobe ip_vs" and try to see if there is /proc/net/ip_vs. If so, your kernel has [[IPVS]] enabled. You can also run "cat /proc/net/ip_vs" or "ipvsadm -Ln" to see the version number of [[IPVS]]. | Try to run "modprobe ip_vs" and try to see if there is /proc/net/ip_vs. If so, your kernel has [[IPVS]] enabled. You can also run "cat /proc/net/ip_vs" or "ipvsadm -Ln" to see the version number of [[IPVS]]. | ||
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| + | == Statistics == | ||
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| + | === How do i get counters from ipvsadm in to create graphs from? === | ||
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| + | ipvsadm --list --stats --numeric --exact | ||
| + | gives you non-human-readable counters for Connections, Packets and Bytes for each Service Address and Realserver. | ||
Revision as of 16:27, 1 March 2006
Contents
General
What's LVS?
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?
Yes, there is a FreeBSD port of IPVS, which supports the LVS/DR and LVS/TUN methods now. See the LVS On FreeBSD page for more information.
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 balance 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.
Performance
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.
Setup
How do I check to see if my kernel has IPVS enabled?
Try to run "modprobe ip_vs" and try to see if there is /proc/net/ip_vs. If so, your kernel has IPVS enabled. You can also run "cat /proc/net/ip_vs" or "ipvsadm -Ln" to see the version number of IPVS.
Statistics
How do i get counters from ipvsadm in to create graphs from?
ipvsadm --list --stats --numeric --exact
gives you non-human-readable counters for Connections, Packets and Bytes for each Service Address and Realserver.
