[android-x86] IP forwarding

http://grokbase.com/t/gg/android-x86/123xvnphgp/ip-forwarding

MatthieuD
Mar 30, 2012 at 1:18 am

hi,

First, thanks for your work, Android-x86 is a great project!

I have compiled ICS generic_x86-eng and I test IP forwarding
functionality. My target has two ethernet ports. I connect two
computers(linux) to these ports.I give their ip:
192.168.0.1
192.168.1.1

In android console, i do :
netcfg eth0 up
ifconfig eth0 192.168.0.2
netcfg eth1 up
ifconfig eth1 192.168.1.2

Android target can ping 192.168.0.1 and 192.168.1.1

Now, i want that 192.168.0.1 can ping 192.168.1.1.

on 192.168.1.1: route add -net 192.168.0.0 netmask 255.255.255.0 gw
192.168.1.2
on 192.168.0.1: route add -net 192.168.1.0 netmask 255.255.255.0 gw
192.168.0.2

And finally on android target: echo 1 > /proc/sys/net/ipv4/conf/all/
forwarding
(/proc/sys/net/ipv4/conf/all/forwarding pass to 1)

Now, on 192.168.1.1, I can ping 192.168.0.2 but not 192.168.0.1.

it seems that IP forwarding doesn't work.

I look in kernel config, but i don't find that can I change..Anyone
got an idea?

+++++++++++++++++++++++++++++++++++++++++

• 6 responses

• Tabletsx86

  at Mar 30, 2012 at 1:42 am

  ⇧

  Ping ethx sends packets only outside the ethx interface and can not
  redirect packet to the internal router
  
  having said that note that "when u ping from your system, the source
  IP is set to INADDR_ANY. And when the kernel finds the destination IP
  to be on the same system, it will simply loopback it. Its using
  loopback (lo) interface"
  
  ref: http://superuser.com/questions/307105/ping-two-ethernet-card-on-the-same-computer-and-on-the-same-subnet
  - Show quoted text -

  reply | permalink

• MatthieuD

  at Mar 31, 2012 at 12:54 am

  ⇧

  OK, as I understand it, this explains why computer 192.168.1.1 can ping
  192.168.0.2.
  
  Now, i want 192.168.0.1 and 192.168.1.1 to ping each other knowing that
  they are on different systems.
  
  
  
  Le jeudi 29 mars 2012 19:42:15 UTC+2, tabletsx86 a écrit :
  - Show quoted text -

  reply | permalink

• Venkatesh bachina

  at Apr 2, 2012 at 12:45 pm

  ⇧

  Hi,
  
  I do have similar problem with Ethernet.
  i am able ping to other system in the network, but cant able to ping to
  others like ping google.com
  or some others.
  
  ping 172.16.5.8
  
  PING 172.16.5.8 (172.16.5.8) 56(84) bytes of data.
  64 bytes from 172.16.5.8: icmp_req=1 ttl=64 time=0.000 ms
  64 bytes from 172.16.5.8: icmp_req=2 ttl=64 time=0.061 ms
  64 bytes from 172.16.5.8: icmp_req=3 ttl=64 time=0.031 ms
  64 bytes from 172.16.5.8: icmp_req=4 ttl=64 time=0.030 ms
  
  apt-get install vim
  
  Reading package lists... Done
  Building dependency tree
  Reading state information... Done
  The following extra packages will be installed:
  libgpm2 libpython2.7 vim-runtime
  Suggested packages:
  gpm ctags vim-doc vim-scripts
  The following NEW packages will be installed:
  libgpm2 libpython2.7 vim vim-runtime
  0 upgraded, 4 newly installed, 0 to remove and 0 not upgraded.
  Need to get 7,813 kB of archives.
  After this operation, 30.3 MB of additional disk space will be used.
  Do you want to continue [Y/n]? Y
  Err http://ports.ubuntu.com/ubuntu-ports/ oneiric/main libgpm2 armel
  1.20.4-3.4ubuntu1
  Temporary failure resolving 'ports.ubuntu.com'
  Err http://ports.ubuntu.com/ubuntu-ports/ oneiric/main libpython2.7 armel
  2.7.2-5ubuntu1
  Temporary failure resolving 'ports.ubuntu.com'
  Err http://ports.ubuntu.com/ubuntu-ports/ oneiric/main vim-runtime all
  2:7.3.154+hg~74503f6ee649-2ubuntu3
  Temporary failure resolving 'ports.ubuntu.com'
  Err http://ports.ubuntu.com/ubuntu-ports/ oneiric/main vim armel
  2:7.3.154+hg~74503f6ee649-2ubuntu3
  Temporary failure resolving 'ports.ubuntu.com'
  Failed to fetch
  http://ports.ubuntu.com/ubuntu-ports/pool/main/g/gpm/libgpm2_1.20.4-3.4ubuntu1_armel.deb
  Temporary failure resolving 'ports.ubuntu.com'
  Failed to fetch
  http://ports.ubuntu.com/ubuntu-ports/pool/main/p/python2.7/libpython2.7_2.7.2-5ubuntu1_armel.deb
  Temporary failure resolving 'ports.ubuntu.com'
  Failed to fetch
  http://ports.ubuntu.com/ubuntu-ports/pool/main/v/vim/vim-runtime_7.3.154+hg~74503f6ee649-2ubuntu3_all.deb
  Temporary failure resolving 'ports.ubuntu.com'
  Failed to fetch
  http://ports.ubuntu.com/ubuntu-ports/pool/main/v/vim/vim_7.3.154+hg~74503f6ee649-2ubuntu3_armel.deb
  Temporary failure resolving 'ports.ubuntu.com'
  E: Unable to fetch some archives, maybe run apt-get update or try with
  --fix-missing?
  
  Any help regarding this network issue....
  
  Thanks in Advance,
  Venky
  - Show quoted text -

  reply | permalink

• MatthieuD

  at Apr 7, 2012 at 2:27 am

  ⇧

  Sorry Venky, but your problem doesn't look like mine.. And I don't
  understand why you try to install ubuntu packages.
  
  On my own, I try exactly the same thing i explain before, but I replace
  Android with Debian, and IP forwarding works..
  
  So, I think something doesn't work on Android?
  
  
  
  
  
  Le jeudi 29 mars 2012 14:41:07 UTC+2, MatthieuD a écrit :
  - Show quoted text -

  reply | permalink

• Venkatesh bachina

  at Apr 9, 2012 at 3:46 pm

  ⇧

  hi math,
  I resolved my issue...
  I forgot to register to dhclient .... (dhclient eth0)
  
  Thanks,
  venky
  - Show quoted text -

  reply | permalink

• Wqq270

  at Jan 6, 2013 at 3:13 pm

  ⇧

  Hi,
  I have the same problem about ip forward in android 4.0. And it works in
  fedora 14 and android 2.3. I don't kown the reason. So I want to kown that
  do you have resolved the issis. Thanks!
  
  在 2012年3月29日星期四UTC+8下午8时41分07秒，MatthieuD写道：
  - Show quoted text -

  reply | permalink