QuickStart (spartiate) Guide
              ------------------------------




0. Pre-Install
  ------------

  * Kernel code only work on vanilla linux kernel 2.6.19 and later
  * Current kernel TCP Splicing implementation doesn t support
    Selective Ack nor Window scaling, please set the following
    values on the system running kernel tcp splicing module :
          . sysctl -w net.ipv4.tcp_sack=0
          . sysctl -w net.ipv4.tcp_dsack=0
          . sysctl -w net.ipv4.tcp_window_scaling=0


I. Installation
  -------------

   Software is split in a userspace daemon called switchd and
a kernelspace module called tcp_splice.

   Kernel module instructions:

   root@devel:~/layer7switch-0.1.2# cd kernel
   root@devel:~/layer7switch-0.1.2# make
   root@devel:~/layer7switch-0.1.2# make install

   Userspace daemon instructions:

   root@devel:~/layer7switch-0.1.2# cd userland/switchd
   root@devel:~/layer7switch-0.1.2# make
   root@devel:~/layer7switch-0.1.2# make install


II. Kernel module tweaking
   -----------------------

    Kernel module export CTL vars and a procfs for connections
entries. CTL vars will give you the opportunity to modify
default TCP FSM timer for state transition:

   root@devel:~/layer7switch-0.1.2# ls /proc/sys/net/tcp_splice
   -rw-r--r-- 1 root root 0 2006-12-11 00:15 debug_level
   -rw-r--r-- 1 root root 0 2006-12-11 00:15 timeout_close
   -rw-r--r-- 1 root root 0 2006-12-11 00:15 timeout_closewait
   -rw-r--r-- 1 root root 0 2006-12-11 00:15 timeout_established
   -rw-r--r-- 1 root root 0 2006-12-11 00:15 timeout_finwait
   -rw-r--r-- 1 root root 0 2006-12-11 00:15 timeout_lastack
   -rw-r--r-- 1 root root 0 2006-12-11 00:15 timeout_listen
   -rw-r--r-- 1 root root 0 2006-12-11 00:15 timeout_synack
   -rw-r--r-- 1 root root 0 2006-12-11 00:15 timeout_synrecv
   -rw-r--r-- 1 root root 0 2006-12-11 00:15 timeout_synsent
   -rw-r--r-- 1 root root 0 2006-12-11 00:15 timeout_timewait

Connection table is accessible through procfs:

   root@devel:~/layer7switch-0.1.2# cat /proc/net/tcp_splice_conn
   FromIP   FPrt ToIP     TPrt LocalIP  LPrt DestIP   DPrt State       Expires
   C0A8C801 A802 C0A8C864 0680 C0A8C864 A85F D41C3001 0050 TIME_WAIT       119
   C0A8C801 A801 C0A8C864 0680 C0A8C864 A85E D41C3001 0050 TIME_WAIT       119
   C0A8C801 A800 C0A8C864 0680 C0A8C864 A85D D41C3001 0050 TIME_WAIT       118


III. Userspace daemon tweaking
    --------------------------

    Current switchd daemon is just a proof of concept. It will just
relay data stream between client and server by processing client
HTTP request in userspace. The daemon currently only support HTTP.
configuration file looks like:

   root@devel:~/layer7switch-0.1.2# cat /etc/switchd/switchd.conf
   ! Configuration file for switchd
   !
   ! Currently we just dont support SACK and WSCALE =8-D
   ! Before using switchd you MUST set :
   !  sysctl -w net.ipv4.tcp_window_scaling=0
   !  sysctl -w net.ipv4.tcp_sack=0
   !  sysctl -w net.ipv4.tcp_dsack=0
   !
   ! valuable stuff can be :
   !  sysctl -w net.ipv4.tcp_tw_recycle=1
   !  sysctl -w net.ipv4.tcp_ecn=0
   !  sysctl -w net.ipv4.tcp_max_syn_backlog=4096

   virtual_server 192.168.200.100 8080 {
   !       schedule_rr                     ! Default scheduler is rr
   !       schedule_lc
   !       listen_backlog 1024             ! Default backlog is 1024
           real_server X.Y.Z.1 80
           real_server X.Y.Z.2 80
           real_server X.Y.Z.3 80
           real_server X.Y.Z.4 80
           real_server X.Y.Z.5 80
   }

   virtual_server 192.168.200.100 8081 {
           real_server X.Y.Z.10 80
   }



Well that's all for the moment :), all feedback and contributions are
welcome ;)

Have fun,
Alexandre