Finding ip address for eth0?

 
Quick Unix question: How do I find out what the IP address for eth0/eth1
is? I thought NetNameResolver>>localHostAddress was supposed to return
this but it returns consistently 127.0.0.1 which is fine from a purity
point of view but utterly useless from any practical perspective ;-)

Is there any way of finding out the IP address for eth0 that doesn't
involve OS process, sed, and grep?

Thanks,
   - Andreas

 

On 26-Aug-09, at 11:50 AM, Andreas Raab wrote:

> NetNameResolver


Well if you have the ipv6 new socket aware VM plus smalltalk code and  
aren't running as useOldNetwork

then the network api deep down uses the class SocketAddressInformation  
and returns an order collection
of which the first entry is choosen as a *best* guess.

an OrderedCollection(
fe80::21c:42ff:fe00:8%en4(Otter-2),
0(0)-inet6-stream-tcp fe80::21c:42ff:fe00:9%en4(fe80::21c:
42ff:fe00:9%en4),
0(0)-inet6-stream-tcp fe80::21b:63ff:fe02:d2db%en4(fe80::21b:
63ff:fe02:d2db%en4),
0(0)-inet6-stream-tcp 10.211.55.2(10.211.55.2),
0(0)-inet4-stream-tcp 10.37.129.2(10.37.129.2),
0(0)-inet4-stream-tcp 192.168.1.139(192.168.1.139),
0(0)-inet4-stream-tcp)

Obviously you want to look deeper than *best guess*

The code appears to call getnameinfo()
But appears to be broken (I think) since

en4: flags=8963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX,MULTICAST>  
mtu 1500
        inet6 fe80::21c:42ff:fe00:8%en4 prefixlen 64 scopeid 0x8
        inet 10.211.55.2 netmask 0xffffff00 broadcast 10.211.55.255
        ether 00:1c:42:00:00:08
        media: autoselect status: active
        supported media: autoselect

but I have a line
0(0)-inet6-stream-tcp 10.211.55.2(10.211.55.2),  saying inet6
yet the inet6 address is fe80::21c:42ff:fe00:8%en4

Unhelpfully the code doesn't return the interface id (in this case  
en4) for IPV4 addresses.
Maybe Ian could fix the bug above if it's a bug, and add the interface  
data for ipv4, well or interface data for ipv4 & 6 if a seperate field  
is needed.
Also I think the results above don't relate much to the actual  
ifconfig -a
See http://bugs.squeak.org/view.php?id=7392

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Grrr  commas in data and in printing the order collection screw the  
interpretation

an OrderedCollection(fe80::21c:42ff:fe00:8%en4(Otter-2),0(0)-inet6-
stream-tcp fe80::21c:42ff:fe00:9%en4(fe80::21c:42ff:fe00:9%en4),0(0)-
inet6-stream-tcp fe80::21b:63ff:fe02:d2db%en4(fe80::21b:63ff:fe02:d2db
%en4),0(0)-inet6-stream-tcp 10.211.55.2(10.211.55.2),0(0)-inet4-stream-
tcp 10.37.129.2(10.37.129.2),0(0)-inet4-stream-tcp  
192.168.1.139(192.168.1.139),0(0)-inet4-stream-tcp)

is really

fe80::21c:42ff:fe00:8%en4(Otter-2),0(0)-inet6-stream-tcp
10.211.55.2(10.211.55.2),0(0)-inet4-stream-tcp
fe80::21b:63ff:fe02:d2db%en4(fe80::21b:63ff:fe02:d2db%en4),0(0)-inet6-
stream-tcp
10.211.55.2(10.211.55.2),0(0)-inet4-stream-tcp
10.37.129.2(10.37.129.2),0(0)-inet4-stream-tcp
192.168.1.139(192.168.1.139),0(0)-inet4-stream-tcp

Still
fe80::21b:63ff:fe02:d2db%en4(fe80::21b:63ff:fe02:d2db%en4),0(0)-inet6-
stream-tcp

is hung off en1 not en4 and shows in ifconfig as  fe80::21b:
63ff:fe02:d2db%en1


On 26-Aug-09, at 11:50 AM, Andreas Raab wrote:

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On 26-Aug-09, at 11:50 AM, Andreas Raab wrote:

> NetNameResolver>>localHostAddress was supposed to return this but it  
> returns consistently 127.0.0.1 which is fine from a purity point of  
> view but utterly useless from any practical perspective ;-)


PS lucky you because the best guess code here gives

NetNameResolver>>localHostAddress


fe80::21c:42ff:fe00:8%en4(Otter-2),0(0)


expecting an IPV4 address?  Tsk...

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2009/8/26 Andreas Raab <[hidden email]>:
>
> Quick Unix question: How do I find out what the IP address for eth0/eth1 is?
> I thought NetNameResolver>>localHostAddress was supposed to return this but
> it returns consistently 127.0.0.1 which is fine from a purity point of view
> but utterly useless from any practical perspective ;-)

I reported exactly this a while ago and was told that the problem is
with me and not the code. Then I suggested that the code would be
changed to directly return 127.0.0.1. That would achieve the same
result more efficiently. Somehow that never got implemented though.

Cheers
Philipe

 
Philippe Marschall wrote:
> 2009/8/26 Andreas Raab <[hidden email]>:
>> Quick Unix question: How do I find out what the IP address for eth0/eth1 is?
>> I thought NetNameResolver>>localHostAddress was supposed to return this but
>> it returns consistently 127.0.0.1 which is fine from a purity point of view
>> but utterly useless from any practical perspective ;-)
>
> I reported exactly this a while ago and was told that the problem is
> with me and not the code.

What was the argument? I'm not trying to find out how a client is
ultimately connecting to the host - I'm trying to make a "best guess"
for a zero configuration environment (concretely: a VMware image with a
single network interface running in a bridged environment). The only
thing that I know for sure is that 127.0.0.1 won't work because clients
won't connect from localhost.

Cheers,
   - Andreas

> Then I suggested that the code would be
> changed to directly return 127.0.0.1. That would achieve the same
> result more efficiently. Somehow that never got implemented though.
>
> Cheers
> Philipe
>

 

On 26.08.2009, at 22:05, Philippe Marschall wrote:

What got implemented though is a primitive to list all interfaces that  
are available. Hosts do not have IP addresses, interfaces do. And  
since hosts typically have multiple interfaces, it's not really up to  
the VM to pick one, but the application.

- Bert -

 
Bert Freudenberg wrote:
> What got implemented though is a primitive to list all interfaces that
> are available. Hosts do not have IP addresses, interfaces do. And since
> hosts typically have multiple interfaces, it's not really up to the VM
> to pick one, but the application.

What's the primitive? How do I use it? Any examples?

Thanks,
   - Andreas

 

On 26.08.2009, at 22:27, Andreas Raab wrote:

> Bert Freudenberg wrote:
>> What got implemented though is a primitive to list all interfaces  
>> that are available. Hosts do not have IP addresses, interfaces do.  
>> And since hosts typically have multiple interfaces, it's not really  
>> up to the VM to pick one, but the application.
>
> What's the primitive? How do I use it? Any examples?


There are examples and tests in the image ... it's part of the IPv6  
work, which did not only add IPv6 support but generalized the Socket  
support. Not sure exactly which method it would be.

- Bert -

 
NetNameResolver addressesForName: self localHostName

but that gives back a list of three address  like
10.37.129.2(10.37.129.2),0(0)-inet4-stream-tcp

but lacking is information about WHICH one is actually usable, the  
192.168.1.139 is the correct one for my office subnet
but 10.211.55.2, and 10.37.129.2 have been setup by Parallels for os-
x,  If I pick 10.211.55.2, or 10.37.129 then things just won't
work since computer B elsewhere in the office doesn't see the 10.*.*.*  
addresses.

Obviously the data coming back has to be a bit more helpful to let the  
smalltalk code pick the right answer.

ifconfig shows

en1: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        inet6 fe80::21b:63ff:fe02:d2db%en1 prefixlen 64 scopeid 0x6
        inet 192.168.1.139 netmask 0xffffff00 broadcast 192.168.1.255
        ether 00:1b:63:02:d2:db
        media: autoselect status: active
        supported media: autoselect

en4: flags=8963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX,MULTICAST>  
mtu 1500
        inet6 fe80::21c:42ff:fe00:8%en4 prefixlen 64 scopeid 0x8
        inet 10.211.55.2 netmask 0xffffff00 broadcast 10.211.55.255
        ether 00:1c:42:00:00:08
        media: autoselect status: active
        supported media: autoselect

en5: flags=8963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX,MULTICAST>  
mtu 1500
        inet6 fe80::21c:42ff:fe00:9%en5 prefixlen 64 scopeid 0x9
        inet 10.37.129.2 netmask 0xffffff00 broadcast 10.37.129.255
        ether 00:1c:42:00:00:09
        media: autoselect status: active
        supported media: autoselect

On 26-Aug-09, at 1:27 PM, Andreas Raab wrote:

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Bert Freudenberg wrote:
Bummer. I thought you were saying that there was "one" primitive that
would do it, not two dozen ;-) Unfortunately, adding the whole IPv6
stuff is not an option at this point; we're too close to release for
that. I think I'll go through the code and try to see how to fold this
into an isolated function - does it work in the OLPC image?

Cheers,
   - Andreas

 
John M McIntosh wrote:
> NetNameResolver addressesForName: self localHostName

This doesn't work at all for me. In fact it's not even asking the right
question ;-) Using the 3.10-6 VM with an Etoys-dev image I get this:

NetNameResolver localHostName
   => 'localhost.localdomain'

NetNameResolver addressesForName: NetNameResolver localHostName
   => 127.0.0.1(localhost),0(0)-inet4-stream-tcp

I'm not surprised with the result because you are asking DNS to resolve
localhost.localdomain which is different from asking the question of
what IP addresses are assigned to the various interfaces in your system.

I thought Bert said that there is a way to enumerate the IP addresses of
the interfaces?

Cheers,
   - Andreas

 

On 26.08.2009, at 23:57, Andreas Raab wrote:


I thought it did, but I never had to use it yet ... grmph, I'm sure  
there is a way. Ian?

- Bert -

 
On Wed, Aug 26, 2009 at 11:50:12AM -0700, Andreas Raab wrote:
>
> Is there any way of finding out the IP address for eth0 that doesn't
> involve OS process, sed, and grep?

Assuming that you're not looking for an elegant solution, you could
figure it out in the start script and pass it to Squeak as a command
line parameter.

  #!/bin/sh
  INTERFACE=eth0
  IPV4_ADDR=`/sbin/ifconfig $INTERFACE | grep 'inet addr' | cut -c21-34`
  echo the IP address on interface $INTERFACE is $IPV4_ADDR
  /usr/local/bin/squeak myimage.image $IPV4_ADDR

Dave

 
David T. Lewis wrote:
> Assuming that you're not looking for an elegant solution, you could
> figure it out in the start script and pass it to Squeak as a command
> line parameter.
>
>   #!/bin/sh
>   INTERFACE=eth0
>   IPV4_ADDR=`/sbin/ifconfig $INTERFACE | grep 'inet addr' | cut -c21-34`
>   echo the IP address on interface $INTERFACE is $IPV4_ADDR
>   /usr/local/bin/squeak myimage.image $IPV4_ADDR

Wow, without sed? I'm impressed ;-) And you know what, that's just what
I'll do. Thanks for the snippet.

Cheers,
   - Andreas

 
Sure well

NetNameResolver localHostName
gives me
'Otter-2.local'

then

NetNameResolver addressesForName: 'Otter-2.local'
gives me back a collection with 6 addresses, but you are saying for
your machine you only get back 1 address?  Lucky you, but will your  
production machine
give back one address, or 23?

I think here the problem is your machine is returning  
'localhost.localdomain'
Oddly on os-x asking for NetNameResolver addressForName:  
'localhost.localdomain'
gives you a primitive failure.

Also as you saw, my localHostName is 'Otter-2.local' which is the  
boujour name http://support.apple.com/kb/TA20999?viewlocale=en_US

Maybe the question is does your computer have a DNS assigned name?


In Pharo  Ian's code  is below, note how the  
SocketAddressInformation>>forHost:... iterates to get all the socket  
info.


addressesForName: hostName
        "NetNameResolver addressesForName: 'impara.de' "
        | adresses |
        adresses := SocketAddressInformation
                forHost: hostName
                service: ''
                flags: 0
                addressFamily: 0
                socketType: SocketAddressInformation socketTypeStream
                protocol: SocketAddressInformation protocolTCP.
        ^adresses


SocketAddressInformation >>forHost: hostName service: servName flags:  
flags addressFamily: family socketType: type protocol: protocol

        | result addr |
        NetNameResolver initializeNetwork.
        NetNameResolver primGetAddressInfoHost: hostName service: servName  
flags: flags family: family type: type protocol: protocol.
        result := OrderedCollection new.
        [(addr := NetNameResolver nextSocketAddressInformation) notNil]  
whileTrue: [result add: addr].
        ^result


On 26-Aug-09, at 2:57 PM, Andreas Raab wrote:

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On 27.08.2009, at 00:15, Andreas Raab wrote:


You might want to set LANG=C in the script. Or be surprised when  
running this on a localized machine.

- Bert -

 
Careful, on my macbook pro, the ethernet port is en0, which is rarely  
used.
But en1 is wireless and mostly used
so the INTERFACE=eth0 is going to be machine dependent


On 26-Aug-09, at 3:15 PM, Andreas Raab wrote:

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On 27.08.2009, at 00:18, John M McIntosh wrote:


This machine has two interfaces (see below).

        NetNameResolver localHostName

gives

        'fedora10'

but

        NetNameResolver addressesForName: NetNameResolver localHostName

still only yields

        an OrderedCollection(127.0.0.1(fedora10),0(spr-itunes)-inet4-stream-
tcp)

That does not sound right indeed.

- Bert -

[bert@fedora10 ~]$ ifconfig
eth0      Link encap:Ethernet  HWaddr 00:0C:29:BF:6D:A7
           inet addr:172.16.22.154  Bcast:172.16.22.255  Mask:
255.255.255.0
           inet6 addr: fe80::20c:29ff:febf:6da7/64 Scope:Link
           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
           RX packets:223095 errors:194711 dropped:0 overruns:0 frame:0
           TX packets:108938 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:1000
           RX bytes:179764576 (171.4 MiB)  TX bytes:76413825 (72.8 MiB)
           Interrupt:19 Base address:0x2024

lo        Link encap:Local Loopback
           inet addr:127.0.0.1  Mask:255.0.0.0
           inet6 addr: ::1/128 Scope:Host
           UP LOOPBACK RUNNING  MTU:16436  Metric:1
           RX packets:38 errors:0 dropped:0 overruns:0 frame:0
           TX packets:38 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:0
           RX bytes:6908 (6.7 KiB)  TX bytes:6908 (6.7 KiB)

 
Thanks but this is not an issue for us. We're talking about an appliance
here, a VMware image that we ship to customers. So by definition LANG=C
and eth0 is the default interface.

Cheers,
   - Andreas

John M McIntosh wrote: