off topic - hope somebody can help

off topic - hope somebody can help

[Alexis]

Does anybody knows why ethernet interfaces stay's up even when i unplug the
ethernet cable?

I have 2 isp connected to a box, with a default route pointing both of them one
using a higer weight to use it as backup conection (using iproute2). Ok, if i
unplug the ethernet cable of eth of isp1 , the ethernet card stays up and nobody
can make any connection. But, if i "really" force the interface shutdown of
provider1 (doing ifdown eth1) the traffic goes instantly trough provider2.

Any idea how can i tear down an interface when i unplug the ethernet cable?

Thanks in advance.

Re: off topic - hope somebody can help

[Jason]

after you yank the cable, what happens if you run mii-tool ethX .  Does it
say that the link is dead? If so, what I do is run mii-tool in monitor
mode and just look for a "link down" statement in syslog. When it arrives,
I down the interface with no cable.  Not the most elegant, but it has
worked for me for some time now.


-- 
       Jason
www.jasonandjessi.com
It gimme the jibblies

On Thu, 10 Jun 2004, Alexis wrote:

> Does anybody knows why ethernet interfaces stay's up even when i unplug the
> ethernet cable?
>
> I have 2 isp connected to a box, with a default route pointing both of them one
> using a higer weight to use it as backup conection (using iproute2). Ok, if i
> unplug the ethernet cable of eth of isp1 , the ethernet card stays up and nobody
> can make any connection. But, if i "really" force the interface shutdown of
> provider1 (doing ifdown eth1) the traffic goes instantly trough provider2.
>
> Any idea how can i tear down an interface when i unplug the ethernet cable?
>
> Thanks in advance.
>
>
>

Re: off topic - hope somebody can help

[Antony Stone]

On Friday 11 June 2004 2:27 am, Alexis wrote:

> Does anybody knows why ethernet interfaces stay's up even when i unplug the
> ethernet cable?

Why shouldn't it?   The interface is still fully functioning even if you 
choose to disconnect it - I think plenty of people would get upset if the 
interface went down on its own just because the cable got unplugged (or the 
hub had a short power failure)...

> I have 2 isp connected to a box, with a default route pointing both of them
> one using a higer weight to use it as backup conection (using iproute2).
> Ok, if i unplug the ethernet cable of eth of isp1 , the ethernet card stays
> up and nobody can make any connection. But, if i "really" force the
> interface shutdown of provider1 (doing ifdown eth1) the traffic goes
> instantly trough provider2.
>
> Any idea how can i tear down an interface when i unplug the ethernet cable?

Personally I would prefer to do something like a ping test to each ISPs 
gateway router - then you can switch routes if any part of the connection 
between your box and the link to the Internet goes down, not just one 
specific piece of CAT5 cable.

Regards,

Antony.

-- 
Documentation is like sex.
When it's good, it's very very good.
When it's bad, it's still better than nothing.

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                                                           please don't CC me.

Re: off topic - hope somebody can help

[Gavin Hamill]

On Friday 11 June 2004 12:29, Antony Stone wrote:

> Why shouldn't it?   The interface is still fully functioning even if you
> choose to disconnect it - I think plenty of people would get upset if the
> interface went down on its own just because the cable got unplugged (or the
> hub had a short power failure)...

This is definately one of the biggest no-brain decisions Microsoft made with 
Windows 2000 - as soon as the link on an Ethernet adapter disappears, all 
open TCP sessions from the workstation are immediately reset.

Multiply that by power-cycling a 48-port switch, and you have a headache :/

gdh

Re: off topic - hope somebody can help

[Antony Stone]

On Friday 11 June 2004 12:42 pm, Gavin Hamill wrote:

> On Friday 11 June 2004 12:29, Antony Stone wrote:
> > Why shouldn't it?   The interface is still fully functioning even if you
> > choose to disconnect it - I think plenty of people would get upset if the
> > interface went down on its own just because the cable got unplugged (or
> > the hub had a short power failure)...
>
> This is definately one of the biggest no-brain decisions Microsoft made
> with Windows 2000 - as soon as the link on an Ethernet adapter disappears,
> all open TCP sessions from the workstation are immediately reset.
>
> Multiply that by power-cycling a 48-port switch, and you have a headache :/

Sheesh - I did not know that - I wrote what I did above on the basis that this 
would be such a stupid and inconvenient thing to do that of course nobody 
would implement it as a standard "feature".

Glad to know that no matter how hard I try, Microsoft still manages to exceed 
my expectations of their inept design concepts.

Antony.

-- 
I think, therefore I am.
I'm pink, therefore I'm Spam.
I drink, therefore I think I am.

                                                     Please reply to the list;
                                                           please don't CC me.

Re: off topic - hope somebody can help

[Damjan]

> Does anybody knows why ethernet interfaces stay's up even when i unplug the
> ethernet cable?
> 
> I have 2 isp connected to a box, with a default route pointing both of them one
> using a higer weight to use it as backup conection (using iproute2). Ok, if i
> unplug the ethernet cable of eth of isp1 , the ethernet card stays up and nobody
> can make any connection. But, if i "really" force the interface shutdown of
> provider1 (doing ifdown eth1) the traffic goes instantly trough provider2.
> 
> Any idea how can i tear down an interface when i unplug the ethernet cable?

you can use netplugd, look it up on freshemat.net.

-- 
damjan | дамјан
This is my jabber ID --> damjan@bagra.net.mk <-- not my mail address!!!

RE: off topic - hope somebody can help

[Alexis]

It could help


-----Mensaje original-----
De: Damjan [mailto:gdamjan@mail.net.mk] 
Enviado el: Viernes, 11 de Junio de 2004 13:55
Para: netfilter@lists.netfilter.org
CC: Alexis
Asunto: Re: off topic - hope somebody can help

> Does anybody knows why ethernet interfaces stay's up even when i unplug
the
> ethernet cable?
> 
> I have 2 isp connected to a box, with a default route pointing both of
them one
> using a higer weight to use it as backup conection (using iproute2). Ok,
if i
> unplug the ethernet cable of eth of isp1 , the ethernet card stays up and
nobody
> can make any connection. But, if i "really" force the interface shutdown
of
> provider1 (doing ifdown eth1) the traffic goes instantly trough provider2.
> 
> Any idea how can i tear down an interface when i unplug the ethernet
cable?

you can use netplugd, look it up on freshemat.net.

-- 
damjan | ??????
This is my jabber ID --> damjan@bagra.net.mk <-- not my mail address!!!

RE: off topic - hope somebody can help

[Hudson Delbert J Contr 61 CS/SCBN]

i think cisco's 'show interface' commands are a model of what s/be
displayed.
these displays delinate between the functionality of the physical interface
and
the protocol that should operating on them.

~piranha@usaf

-----Original Message-----
From: netfilter-admin@lists.netfilter.org
[mailto:netfilter-admin@lists.netfilter.org]On Behalf Of Antony Stone
Sent: Friday, June 11, 2004 5:01 AM
To: netfilter@lists.netfilter.org
Subject: Re: off topic - hope somebody can help


On Friday 11 June 2004 12:42 pm, Gavin Hamill wrote:

> On Friday 11 June 2004 12:29, Antony Stone wrote:
> > Why shouldn't it?   The interface is still fully functioning even if you
> > choose to disconnect it - I think plenty of people would get upset if
the
> > interface went down on its own just because the cable got unplugged (or
> > the hub had a short power failure)...
>
> This is definately one of the biggest no-brain decisions Microsoft made
> with Windows 2000 - as soon as the link on an Ethernet adapter disappears,
> all open TCP sessions from the workstation are immediately reset.
>
> Multiply that by power-cycling a 48-port switch, and you have a headache
:/

Sheesh - I did not know that - I wrote what I did above on the basis that
this 
would be such a stupid and inconvenient thing to do that of course nobody 
would implement it as a standard "feature".

Glad to know that no matter how hard I try, Microsoft still manages to
exceed 
my expectations of their inept design concepts.

Antony.

-- 
I think, therefore I am.
I'm pink, therefore I'm Spam.
I drink, therefore I think I am.

                                                     Please reply to the
list;
                                                           please don't CC
me.

RE: off topic - hope somebody can help

[Alexis]

Lets see, Im aware that "shut" an interface when I unplug the network cable
is a stupid thing to do. But im not asking about this.

Im asking about to "tear down" the protocol of the interface, so I can loose
all the routes of this link and the traffic switch directly to second isp.
I don’t care really if I unplug the cable the Ethernet card remains up, I
need the routes disappear in order to switch to the other isp.

I has nothing to deal with Microsoft, linux or whatever.

Like this mail say, when you make a show int in cisco routers there's a link
state and a protocol state. If protocol goes down (one reason could be
unplug the cable) the routes are lost.


This is what I need, and additional to this, some distributions shows in the
console a link notice and some don’t, I assume this is related to the nic
driver.



-----Mensaje original-----
De: netfilter-admin@lists.netfilter.org
[mailto:netfilter-admin@lists.netfilter.org] En nombre de Hudson Delbert J
Contr 61 CS/SCBN
Enviado el: Viernes, 11 de Junio de 2004 12:48
Para: 'netfilter@lists.netfilter.org'
Asunto: RE: off topic - hope somebody can help

i think cisco's 'show interface' commands are a model of what s/be
displayed.
these displays delinate between the functionality of the physical interface
and
the protocol that should operating on them.

~piranha@usaf

-----Original Message-----
From: netfilter-admin@lists.netfilter.org
[mailto:netfilter-admin@lists.netfilter.org]On Behalf Of Antony Stone
Sent: Friday, June 11, 2004 5:01 AM
To: netfilter@lists.netfilter.org
Subject: Re: off topic - hope somebody can help


On Friday 11 June 2004 12:42 pm, Gavin Hamill wrote:

> On Friday 11 June 2004 12:29, Antony Stone wrote:
> > Why shouldn't it?   The interface is still fully functioning even if you
> > choose to disconnect it - I think plenty of people would get upset if
the
> > interface went down on its own just because the cable got unplugged (or
> > the hub had a short power failure)...
>
> This is definately one of the biggest no-brain decisions Microsoft made
> with Windows 2000 - as soon as the link on an Ethernet adapter disappears,
> all open TCP sessions from the workstation are immediately reset.
>
> Multiply that by power-cycling a 48-port switch, and you have a headache
:/

Sheesh - I did not know that - I wrote what I did above on the basis that
this 
would be such a stupid and inconvenient thing to do that of course nobody 
would implement it as a standard "feature".

Glad to know that no matter how hard I try, Microsoft still manages to
exceed 
my expectations of their inept design concepts.

Antony.

-- 
I think, therefore I am.
I'm pink, therefore I'm Spam.
I drink, therefore I think I am.

                                                     Please reply to the
list;
                                                           please don't CC
me.