ubuntu 12.04 : configure LVS ( Linux Virtual Server )

client ( 192.168.10.14 ) -- VIP 192.168.10.112 LVS 192.168.30.111 -- Web*2 192.168.30.10 , 20

                          interface IP 192.168.10.225

install LVS

# apt-get install ipvsadm libnl1

enable IP forwarding

# echo 1 > /proc/sys/net/ipv4/ip_forward # echo 0 > /proc/sys/net/ipv4/conf/all/rp_filter

reflect above settings permanently

# egrep ip_forward /etc/sysctl.conf net.ipv4.ip_forward=1

assign VIP

# ip addr add 192.168.10.112 label eth0:vip dev eth0 # ip addr show eth0 label eth0:vip    inet 192.168.10.112/32 scope global eth0:vip

configure LVS with ipvsadm command.

# ipvsadm -A -t 192.168.10.112:80 -s rr # ipvsadm -a -t 192.168.10.112:80 -r 192.168.30.10:80 -m -w 1 # ipvsadm -a -t 192.168.10.112:80 -r 192.168.30.20:80 -m -w 1 # ipvsadm -Ln IP Virtual Server version 1.2.1 (size=4096) Prot LocalAddress:Port Scheduler Flags  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn TCP  192.168.10.122:80 rr  -> 192.168.30.10:80             Masq    1      0          0  -> 192.168.30.20:80             Masq    1      0          0

# ipvsadm -ln --rate IP Virtual Server version 1.2.1 (size=4096) Prot LocalAddress:Port                 CPS    InPPS   OutPPS    InBPS   OutBPS  -> RemoteAddress:Port TCP  192.168.10.112:80                  57      342      285    25908    31045  -> 192.168.30.10:80                   29      171      143    12957    15525  -> 192.168.30.20:80                   29      171      143    12952    15519

cap data between client and LVS

# tshark -i eth0 port 80 Capturing on eth0  0.000000 192.168.10.14 -> 192.168.10.112 TCP 74 54695 > http [SYN] Seq=0 Win=14600 Len=0 MSS=1460 SACK_PERM=1 TSval=289451261 TSecr=0 WS=128  0.000591 192.168.10.112 -> 192.168.10.14 TCP 74 http > 54695 [SYN, ACK] Seq=0 Ack=1 Win=14480 Len=0 MSS=1460 SACK_PERM=1 TSval=356120740 TSecr=289451261 WS=32  0.000825 192.168.10.14 -> 192.168.10.112 TCP 66 54695 > http [ACK] Seq=1 Ack=1 Win=14720 Len=0 TSval=289451261 TSecr=356120740  0.000883 192.168.10.14 -> 192.168.10.112 HTTP 180 GET / HTTP/1.1  0.001312 192.168.10.112 -> 192.168.10.14 TCP 66 http > 54695 [ACK] Seq=1 Ack=115 Win=14496 Len=0 TSval=356120740 TSecr=289451261  0.001646 192.168.10.112 -> 192.168.10.14 HTTP 342 HTTP/1.1 200 OK  (text/html)  0.001672 192.168.10.112 -> 192.168.10.14 TCP 66 http > 54695 [FIN, ACK] Seq=277 Ack=115 Win=14496 Len=0 TSval=356120741 TSecr=289451261  0.001878 192.168.10.14 -> 192.168.10.112 TCP 66 54695 > http [ACK] Seq=115 Ack=277 Win=15744 Len=0 TSval=289451262 TSecr=356120741  0.002299 192.168.10.14 -> 192.168.10.112 TCP 66 54695 > http [FIN, ACK] Seq=115 Ack=278 Win=15744 Len=0 TSval=289451262 TSecr=356120741  0.002799 192.168.10.112 -> 192.168.10.14 TCP 66 http > 54695 [ACK] Seq=278 Ack=116 Win=14496 Len=0 TSval=356120742 TSecr=289451262

cap data between LVS and Web servers

# tshark -i eth1 port 80 Capturing on eth1  0.000000 192.168.10.14 -> 192.168.30.10 TCP 74 54696 > http [SYN] Seq=0 Win=14600 Len=0 MSS=1460 SACK_PERM=1 TSval=289453429 TSecr=0 WS=128  0.000559 192.168.30.10 -> 192.168.10.14 TCP 74 http > 54696 [SYN, ACK] Seq=0 Ack=1 Win=14480 Len=0 MSS=1460 SACK_PERM=1 TSval=356177805 TSecr=289453429 WS=32  0.000816 192.168.10.14 -> 192.168.30.10 TCP 66 54696 > http [ACK] Seq=1 Ack=1 Win=14720 Len=0 TSval=289453429 TSecr=356177805  0.000869 192.168.10.14 -> 192.168.30.10 HTTP 180 GET / HTTP/1.1  0.001283 192.168.30.10 -> 192.168.10.14 TCP 66 http > 54696 [ACK] Seq=1 Ack=115 Win=14496 Len=0 TSval=356177805 TSecr=289453429  0.001685 192.168.30.10 -> 192.168.10.14 HTTP 342 HTTP/1.1 200 OK  (text/html)  0.001715 192.168.30.10 -> 192.168.10.14 TCP 66 http > 54696 [FIN, ACK] Seq=277 Ack=115 Win=14496 Len=0 TSval=356177806 TSecr=289453429  0.001922 192.168.10.14 -> 192.168.30.10 TCP 66 54696 > http [ACK] Seq=115 Ack=277 Win=15744 Len=0 TSval=289453430 TSecr=356177806  0.002273 192.168.10.14 -> 192.168.30.10 TCP 66 54696 > http [FIN, ACK] Seq=115 Ack=278 Win=15744 Len=0 TSval=289453430 TSecr=356177806  0.002771 192.168.30.10 -> 192.168.10.14 TCP 66 http > 54696 [ACK] Seq=278 Ack=116 Win=14496 Len=0 TSval=356177807 TSecr=289453430