[gentoo-user] Network problem with linux server

[gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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Hi All.

This problem is not strictly related to gentoo, however I'm sure someone
here will be able to help me in some way: sorry if I bother you!

I'm having a really strange problem: for some reason, everytime I reboot my
server, the default gateway gets attached to the 'lo' interface, even if I
correctly attached it to the eth0 device.

I fixed the problem editing the /etc/sysconfig/network file and adding

GATEWAY=195.75.145.1
GATEWAYDEV=eth0

however I'm not sure this is the solution: I already configured the default
gateway only in the ifcfg-eth0 file!

After this, I have an even worse problem: doing an ssh 195.75.145.1, I get
an answer from my own server like if it was a loopback address !

Here is the output of ifconfig:

eth0      Link encap:Ethernet  HWaddr 5C:F3:FC:55:63:42
          inet addr:195.75.145.122  Bcast:195.75.145.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:4281 errors:0 dropped:0 overruns:0 frame:0
          TX packets:25 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:4934949 (4.7 MiB)  TX bytes:2133 (2.0 KiB)
          Interrupt:28 Memory:92000000-92012800

eth2      Link encap:Ethernet  HWaddr 00:1B:21:8E:0A:86
          inet addr:192.168.19.95  Bcast:192.168.19.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:2049 errors:0 dropped:0 overruns:0 frame:0
          TX packets:917 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:236160 (230.6 KiB)  TX bytes:99635 (97.2 KiB)
          Memory:97d80000-97e00000

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:56 errors:0 dropped:0 overruns:0 frame:0
          TX packets:56 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:7714 (7.5 KiB)  TX bytes:7714 (7.5 KiB)

lo:0      Link encap:Local Loopback
          inet addr:195.75.145.120  Mask:255.255.255.0
          UP LOOPBACK RUNNING  MTU:16436  Metric:1

here is the output of ip route

192.168.19.0/24 dev eth2  proto kernel  scope link  src 192.168.19.95
195.75.145.0/24 dev eth0  proto kernel  scope link  src 195.75.145.122
169.254.0.0/16 dev eth0  scope link  metric 1002
169.254.0.0/16 dev eth2  scope link  metric 1004
default via 195.75.145.1 dev eth0

Please!! Do you have any advice?

Thanks,
Massimiliano

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Re: [gentoo-user] Network problem with linux server

[J. Roeleveld]

On Mon, November 7, 2011 12:13 pm, Massimiliano Ziccardi wrote:
> Hi All.
>
> This problem is not strictly related to gentoo, however I'm sure someone
> here will be able to help me in some way: sorry if I bother you!
>
> I'm having a really strange problem: for some reason, everytime I reboot
> my
> server, the default gateway gets attached to the 'lo' interface, even if I
> correctly attached it to the eth0 device.
>
> I fixed the problem editing the /etc/sysconfig/network file and adding
>
> GATEWAY=195.75.145.1
> GATEWAYDEV=eth0
>
> however I'm not sure this is the solution: I already configured the
> default
> gateway only in the ifcfg-eth0 file!

Which Linux distribution are you using?
Gentoo does not use those files.

Try editing the /etc/conf.d/net file to match your network settings.

--
Joost

Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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You are totally right: I'm not using gentoo, but I'm serching for help and
gentoo's mailing list is the most technical one: I'm truly sorry for the OT.

Just some hint about what could be wrong or some command to launch to
understand what's wrong would be great: I'm getting crazy!!

My distribution is CENTOS but couldn't get much help there, so I tried here.

Thanks a lot!

Massimiliano

On Mon, Nov 7, 2011 at 12:24, J. Roeleveld <joost@antarean.org> wrote:

> On Mon, November 7, 2011 12:13 pm, Massimiliano Ziccardi wrote:
> > Hi All.
> >
> > This problem is not strictly related to gentoo, however I'm sure someone
> > here will be able to help me in some way: sorry if I bother you!
> >
> > I'm having a really strange problem: for some reason, everytime I reboot
> > my
> > server, the default gateway gets attached to the 'lo' interface, even if
> I
> > correctly attached it to the eth0 device.
> >
> > I fixed the problem editing the /etc/sysconfig/network file and adding
> >
> > GATEWAY=195.75.145.1
> > GATEWAYDEV=eth0
> >
> > however I'm not sure this is the solution: I already configured the
> > default
> > gateway only in the ifcfg-eth0 file!
>
> Which Linux distribution are you using?
> Gentoo does not use those files.
>
> Try editing the /etc/conf.d/net file to match your network settings.
>
> --
> Joost
>
>
>

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Re: [gentoo-user] Network problem with linux server

[J. Roeleveld]

Please do NOT top-post.

On Mon, November 7, 2011 12:34 pm, Massimiliano Ziccardi wrote:
> You are totally right: I'm not using gentoo, but I'm serching for help and
> gentoo's mailing list is the most technical one: I'm truly sorry for the
> OT.

If asking questions on how to do things on non-Gentoo installations,
please always mention the distribution in your email.
>
> Just some hint about what could be wrong or some command to launch to
> understand what's wrong would be great: I'm getting crazy!!
>
> My distribution is CENTOS but couldn't get much help there, so I tried
> here.

What about the documentation?
I have noticed that most binary distros require the use of their graphical
admin tools to make any changes to the configuration.

--
Joost

Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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>
> Please do NOT top-post


Sorry.

If asking questions on how to do things on non-Gentoo installations,
> please always mention the distribution in your email.


Ok, sorry again!

What about the documentation?
> I have noticed that most binary distros require the use of their graphical
> admin tools to make any changes to the configuration.


I read the documentation and tried to carefully follow it. Now I'm getting
this strange behaviour and don't know what's happening.
I tried both editing the config files and using the network config tool,
but with no luck.

I thought it was a routing problem, but as you can see, the routes I sent
seems to be ok.

However, I'm not a networking guru, so I don't know what to look else.
Maybe the arp tables?

Here is the arptables -L output:

Chain IN (policy ACCEPT)
target     source-ip            destination-ip       source-hw
 destination-hw     hlen   op         hrd        pro

Chain OUT (policy ACCEPT)
target     source-ip            destination-ip       source-hw
 destination-hw     hlen   op         hrd        pro

Chain FORWARD (policy ACCEPT)
target     source-ip            destination-ip       source-hw
 destination-hw     hlen   op         hrd        pro

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Re: [gentoo-user] Network problem with linux server

[Michael Schreckenbauer]

Hi,

Am Montag, 7. November 2011, 13:15:53 schrieb Massimiliano Ziccardi:
> I thought it was a routing problem, but as you can see, the routes I sent
> seems to be ok.

you have those link-local entries in your routes (169.254.0.0/16), Try adding 
NOZEROCONF= yes to /etc/sysconfig/network

Best,
Michael

Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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Hi All.

>The routes and ifconfig seems correct to me.

>How is the router configured?
>I specifically mean, does it have any firewall configurations redirecting
>SSH-traffic to your machine?

I don't have access to the routers, however they are used for many other
servers too.
Moreover, I tried the ssh command because I wanted to be sure I was pinging
the right servers (for some reason they can't ping me!) and I discovered
that I was pinging myself.

Moreover I'm trying to ping/ssh on servers that are on the same lan and the
network technician (?!) assured me there is no firewall between my server
and, for example, 195.75.145.33.

Another strange thing I noticed is that :

   1. 195.75.146.104 (that passes through a firewall!!) is able to ping my
   server
   2. 195.75.145.33 (that is on the same net without firewall) is not able
   to ping my server

I have the dubt something strange happens in the routers/switch, etc.
However, since I have that strange behaviour on my machine (ping itself,
etc.), thay says my server is bad configured.

Moreover, 195.75.145.33 is able to ping many other servers on the same net
but mine.

Don't know what else to do...

Regards,
Massimiliano

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Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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> you have those link-local entries in your routes (169.254.0.0/16), Try
> adding
> NOZEROCONF= yes to /etc/sysconfig/network


Already tried, but no luck...

Thanks,
Massimiliano

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Re: [gentoo-user] Network problem with linux server

[Michael Schreckenbauer]

Am Montag, 7. November 2011, 13:47:49 schrieb Massimiliano Ziccardi:
> > you have those link-local entries in your routes (169.254.0.0/16), Try
> > adding
> > NOZEROCONF= yes to /etc/sysconfig/network
> 
> Already tried, but no luck...

could you post  the output of
ip route
with zeroconf disabled?

> Thanks,
> Massimiliano

Best,
Michael

Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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>
> could you post  the output of
> ip route
> with zeroconf disabled?


Here it is!

192.168.19.0/24 dev eth2  proto kernel  scope link  src 192.168.19.95
195.75.145.0/24 dev eth0  proto kernel  scope link  src 195.75.145.122
default via 195.75.145.1 dev eth0


Thanks,
Massimiliano

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Re: [gentoo-user] Network problem with linux server

[Michael Schreckenbauer]

Am Montag, 7. November 2011, 14:15:39 schrieb Massimiliano Ziccardi:
> > could you post  the output of
> > ip route
> > with zeroconf disabled?
> 
> Here it is!
> 
> 192.168.19.0/24 dev eth2  proto kernel  scope link  src 192.168.19.95
> 195.75.145.0/24 dev eth0  proto kernel  scope link  src 195.75.145.122
> default via 195.75.145.1 dev eth0

seems to be a really tricky one...
What does
tracepath 195.75.145.33
give?

> Thanks,
> Massimiliano

Best,
Michael

Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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>
> seems to be a really tricky one...
> What does
> tracepath 195.75.145.33
> give?


Here is the output:

 1:  195.75.145.33 (195.75.145.33)                          0.074ms pmtu
16436
 1:  195.75.145.33 (195.75.145.33)                          0.039ms reached
 1:  195.75.145.33 (195.75.145.33)                          0.028ms reached

I tried shutting down localhost with:

ifconfig lo down.

Now I can't ping 195.75.145.33 anymore (as all the other 195.75.145.xx
addresses).

And now tracepath gives:

1:  send failed
     Resume: pmtu 65535

So, for some reason, seems it always uses the 'lo' device...

Any idea?

Regards,
Massimiliano

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Re: [gentoo-user] Network problem with linux server

[Pandu Poluan]

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On Nov 7, 2011 8:38 PM, "Massimiliano Ziccardi" <
massimiliano.ziccardi@gmail.com> wrote:
>>
>> seems to be a really tricky one...
>> What does
>> tracepath 195.75.145.33
>> give?
>
>
> Here is the output:
>
>  1:  195.75.145.33 (195.75.145.33)                          0.074ms pmtu
16436
>  1:  195.75.145.33 (195.75.145.33)                          0.039ms
reached
>  1:  195.75.145.33 (195.75.145.33)                          0.028ms
reached
>
> I tried shutting down localhost with:
>
> ifconfig lo down.
>
> Now I can't ping 195.75.145.33 anymore (as all the other 195.75.145.xx
addresses).
>
> And now tracepath gives:
>
> 1:  send failed
>      Resume: pmtu 65535
>
> So, for some reason, seems it always uses the 'lo' device...
>
> Any idea?
>

I've been deploying multi-interface Linux gateways since 2008, so I'll try.

Please post:

- output of ip rule sh
- output of ip route sh table $t, where $t is *all* table names/numbers you
get from the first output ( "... lookup $t" )

Rgds,

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Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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>
> I've been deploying multi-interface Linux gateways since 2008, so I'll try.
> Please post:
> - output of ip rule sh


# ip rule sh
0:      from all lookup local
32766:  from all lookup main
32767:  from all lookup default

# ip route sh table 0
192.168.19.0/24 dev eth2  proto kernel  scope link  src 192.168.19.95
195.75.145.0/24 dev eth0  proto kernel  scope link  src 195.75.145.122
default via 195.75.145.1 dev lo  scope link
broadcast 127.255.255.255 dev lo  table local  proto kernel  scope link
 src 127.0.0.1
local 195.75.145.122 dev eth0  table local  proto kernel  scope host  src
195.75.145.122
broadcast 192.168.19.0 dev eth2  table local  proto kernel  scope link  src
192.168.19.95
broadcast 195.75.145.255 dev eth0  table local  proto kernel  scope link
 src 195.75.145.122
broadcast 195.75.145.255 dev lo  table local  proto kernel  scope link  src
195.75.145.120
local 195.75.145.120 dev lo  table local  proto kernel  scope host  src
195.75.145.120
local 192.168.19.95 dev eth2  table local  proto kernel  scope host  src
192.168.19.95
broadcast 192.168.19.255 dev eth2  table local  proto kernel  scope link
 src 192.168.19.95
broadcast 195.75.145.0 dev eth0  table local  proto kernel  scope link  src
195.75.145.122
broadcast 195.75.145.0 dev lo  table local  proto kernel  scope link  src
195.75.145.120
broadcast 127.0.0.0 dev lo  table local  proto kernel  scope link  src
127.0.0.1
local 127.0.0.1 dev lo  table local  proto kernel  scope host  src 127.0.0.1
local 195.75.145.0/24 dev lo  table local  proto kernel  scope host  src
195.75.145.120
local 127.0.0.0/8 dev lo  table local  proto kernel  scope host  src
127.0.0.1

# ip route sh table 32766
# ip route sh table 32767

Both 32766 and 32767 are empty....

Thanks very much!

Regards,
Massimiliano



On Mon, Nov 7, 2011 at 14:59, Pandu Poluan <pandu@poluan.info> wrote:

>
> On Nov 7, 2011 8:38 PM, "Massimiliano Ziccardi" <
> massimiliano.ziccardi@gmail.com> wrote:
> >>
> >> seems to be a really tricky one...
> >> What does
> >> tracepath 195.75.145.33
> >> give?
> >
> >
> > Here is the output:
> >
> >  1:  195.75.145.33 (195.75.145.33)                          0.074ms pmtu
> 16436
> >  1:  195.75.145.33 (195.75.145.33)                          0.039ms
> reached
> >  1:  195.75.145.33 (195.75.145.33)                          0.028ms
> reached
> >
> > I tried shutting down localhost with:
> >
> > ifconfig lo down.
> >
> > Now I can't ping 195.75.145.33 anymore (as all the other 195.75.145.xx
> addresses).
> >
> > And now tracepath gives:
> >
> > 1:  send failed
> >      Resume: pmtu 65535
> >
> > So, for some reason, seems it always uses the 'lo' device...
> >
> > Any idea?
> >
>
> I've been deploying multi-interface Linux gateways since 2008, so I'll try.
>
> Please post:
>
> - output of ip rule sh
> - output of ip route sh table $t, where $t is *all* table names/numbers
> you get from the first output ( "... lookup $t" )
>
> Rgds,
>

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Re: [gentoo-user] Network problem with linux server

[Pandu Poluan]

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I'm going to highlight anomalous routes, those that have no business in the
local table.

On Nov 7, 2011 9:14 PM, "Massimiliano Ziccardi" <
massimiliano.ziccardi@gmail.com> wrote:
>>
>> I've been deploying multi-interface Linux gateways since 2008, so I'll
try.
>> Please post:
>> - output of ip rule sh
>
>
> # ip rule sh
> 0:      from all lookup local
> 32766:  from all lookup main
> 32767:  from all lookup default
>
> # ip route sh table 0
> 192.168.19.0/24 dev eth2  proto kernel  scope link  src 192.168.19.95
> 195.75.145.0/24 dev eth0  proto kernel  scope link  src 195.75.145.122
> default via 195.75.145.1 dev lo  scope link

These 3 should be in main. In addition, default must not go through dev lo.

> local 195.75.145.0/24 dev lo  table local  proto kernel  scope host  src
195.75.145.120

This is also highly suspect: a subnet should be attached to an ethX dev,
not dev lo. Except 127.0.0.0/8

> # ip route sh table 32766
> # ip route sh table 32767
>
> Both 32766 and 32767 are empty....
>

It's normal for 32767 to be empty, but very irregular for main to be empty.

Rgds,

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Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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Sorry, I sent you the wrong output of ip route sh table 0.

Follows the right one (sorry!)

# ip route sh table 0
192.168.19.0/24 dev eth2  proto kernel  scope link  src 192.168.19.95
195.75.145.0/24 dev eth0  proto kernel  scope link  src 195.75.145.122
default via 195.75.145.1 dev eth0
broadcast 127.255.255.255 dev lo  table local  proto kernel  scope link
 src 127.0.0.1
local 195.75.145.122 dev eth0  table local  proto kernel  scope host  src
195.75.145.122
broadcast 192.168.19.0 dev eth2  table local  proto kernel  scope link  src
192.168.19.95
broadcast 195.75.145.255 dev eth0  table local  proto kernel  scope link
 src 195.75.145.122
broadcast 195.75.145.255 dev lo  table local  proto kernel  scope link  src
195.75.145.120
local 195.75.145.120 dev lo  table local  proto kernel  scope host  src
195.75.145.120
local 192.168.19.95 dev eth2  table local  proto kernel  scope host  src
192.168.19.95
broadcast 192.168.19.255 dev eth2  table local  proto kernel  scope link
 src 192.168.19.95
broadcast 195.75.145.0 dev eth0  table local  proto kernel  scope link  src
195.75.145.122
broadcast 195.75.145.0 dev lo  table local  proto kernel  scope link  src
195.75.145.120
broadcast 127.0.0.0 dev lo  table local  proto kernel  scope link  src
127.0.0.1
local 127.0.0.1 dev lo  table local  proto kernel  scope host  src 127.0.0.1
local 195.75.145.0/24 dev lo  table local  proto kernel  scope host  src
195.75.145.120
local 127.0.0.0/8 dev lo  table local  proto kernel  scope host  src
127.0.0.1

Regards,
Massimiliano

On Mon, Nov 7, 2011 at 14:59, Pandu Poluan <pandu@poluan.info> wrote:

>
> On Nov 7, 2011 8:38 PM, "Massimiliano Ziccardi" <
> massimiliano.ziccardi@gmail.com> wrote:
> >>
> >> seems to be a really tricky one...
> >> What does
> >> tracepath 195.75.145.33
> >> give?
> >
> >
> > Here is the output:
> >
> >  1:  195.75.145.33 (195.75.145.33)                          0.074ms pmtu
> 16436
> >  1:  195.75.145.33 (195.75.145.33)                          0.039ms
> reached
> >  1:  195.75.145.33 (195.75.145.33)                          0.028ms
> reached
> >
> > I tried shutting down localhost with:
> >
> > ifconfig lo down.
> >
> > Now I can't ping 195.75.145.33 anymore (as all the other 195.75.145.xx
> addresses).
> >
> > And now tracepath gives:
> >
> > 1:  send failed
> >      Resume: pmtu 65535
> >
> > So, for some reason, seems it always uses the 'lo' device...
> >
> > Any idea?
> >
>
> I've been deploying multi-interface Linux gateways since 2008, so I'll try.
>
> Please post:
>
> - output of ip rule sh
> - output of ip route sh table $t, where $t is *all* table names/numbers
> you get from the first output ( "... lookup $t" )
>
> Rgds,
>

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Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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Maybe I found where the problem is!
Shutting down lo:0 everything seems to work properly!

However I need to configure lo:0 for local triangulation (balancing through
RADWARE): how should I configure it to not conflict with the other network
cards?

Thanks!

Massimiliano Ziccardi

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Re: [gentoo-user] Network problem with linux server

[Michael Schreckenbauer]

Am Montag, 7. November 2011, 15:20:12 schrieb Massimiliano Ziccardi:
> Maybe I found where the problem is!
> Shutting down lo:0 everything seems to work properly!
> However I need to configure lo:0 for local triangulation (balancing through
> RADWARE): how should I configure it to not conflict with the other network
> cards?

try assigning a netmask of 255.255.255.255 to it.

> Thanks!
> Massimiliano Ziccardi

Best,
Michael

Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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>
> try assigning a netmask of 255.255.255.255 to it.


Seems to work!
I'm asking to the network administrators if 255.255.255.255 is ok !

I'll let you know!

Thank you all! Gentoo's mailing list il always the best one!

Thanks!

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Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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they told me 255.255.255.255 is ok....

I really thank you all very much for your support!

Regards,
Massimiliano

On Mon, Nov 7, 2011 at 15:48, Massimiliano Ziccardi <
massimiliano.ziccardi@gmail.com> wrote:

> try assigning a netmask of 255.255.255.255 to it.
>
>
> Seems to work!
> I'm asking to the network administrators if 255.255.255.255 is ok !
>
> I'll let you know!
>
> Thank you all! Gentoo's mailing list il always the best one!
>
> Thanks!
>
>

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Re: [gentoo-user] Network problem with linux server

[Pandu Poluan]

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On Nov 7, 2011 10:17 PM, "Massimiliano Ziccardi" <
massimiliano.ziccardi@gmail.com> wrote:
>
> they told me 255.255.255.255 is ok....
>
> I really thank you all very much for your support!
>

Cool! That should solve the problem of a subnet being associated to dev lo

Anyways, this is also a good knowledge for me :-)

Rgds,

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Re: [gentoo-user] Network problem with linux server

[Michael Schreckenbauer]

Am Montag, 7. November 2011, 14:35:46 schrieb Massimiliano Ziccardi:
> > seems to be a really tricky one...
> > What does
> > tracepath 195.75.145.33
> > give?
> 
> Here is the output:
> 
>  1:  195.75.145.33 (195.75.145.33)                          0.074ms pmtu
> 16436
>  1:  195.75.145.33 (195.75.145.33)                          0.039ms reached
>  1:  195.75.145.33 (195.75.145.33)                          0.028ms reached
> 
> I tried shutting down localhost with:
> 
> ifconfig lo down.
> 
> Now I can't ping 195.75.145.33 anymore (as all the other 195.75.145.xx
> addresses).
> 
> And now tracepath gives:
> 
> 1:  send failed
>      Resume: pmtu 65535
> 
> So, for some reason, seems it always uses the 'lo' device...
> 
> Any idea?

I noticed lo:0 is on the same net and has the same netmask as eth0.
Where does lo:0 come from? Is it needed?
I have no idea, if this is the problem or even related, just wondering.

> Regards,
> Massimiliano

Best,
Michael

Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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Our network admin told me to create a lo:0 to that address to create a VIP
to be balanced by the network load balancer.

That is why lo:0 is there...

Thanks!

Regards,
Massimiliano Ziccardi

On Mon, Nov 7, 2011 at 15:01, Michael Schreckenbauer <grimlog@gmx.de> wrote:

> Am Montag, 7. November 2011, 14:35:46 schrieb Massimiliano Ziccardi:
> > > seems to be a really tricky one...
> > > What does
> > > tracepath 195.75.145.33
> > > give?
> >
> > Here is the output:
> >
> >  1:  195.75.145.33 (195.75.145.33)                          0.074ms pmtu
> > 16436
> >  1:  195.75.145.33 (195.75.145.33)                          0.039ms
> reached
> >  1:  195.75.145.33 (195.75.145.33)                          0.028ms
> reached
> >
> > I tried shutting down localhost with:
> >
> > ifconfig lo down.
> >
> > Now I can't ping 195.75.145.33 anymore (as all the other 195.75.145.xx
> > addresses).
> >
> > And now tracepath gives:
> >
> > 1:  send failed
> >      Resume: pmtu 65535
> >
> > So, for some reason, seems it always uses the 'lo' device...
> >
> > Any idea?
>
> I noticed lo:0 is on the same net and has the same netmask as eth0.
> Where does lo:0 come from? Is it needed?
> I have no idea, if this is the problem or even related, just wondering.
>
> > Regards,
> > Massimiliano
>
> Best,
> Michael
>
>
>

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Re: [gentoo-user] Network problem with linux server

[J. Roeleveld]

On Mon, November 7, 2011 1:15 pm, Massimiliano Ziccardi wrote:
> What about the documentation?
>> I have noticed that most binary distros require the use of their
>> graphical
>> admin tools to make any changes to the configuration.
>
>
> I read the documentation and tried to carefully follow it. Now I'm getting
> this strange behaviour and don't know what's happening.
> I tried both editing the config files and using the network config tool,
> but with no luck.
>
> I thought it was a routing problem, but as you can see, the routes I sent
> seems to be ok.

The routes and ifconfig seems correct to me.

How is the router configured?
I specifically mean, does it have any firewall configurations redirecting
SSH-traffic to your machine?

--
Joost

Re: [gentoo-user] Network problem with linux server

[Jonas de Buhr]

Am 07/11/2011 12:13, schrieb Massimiliano Ziccardi:
> Hi All.
[SNIP]
> Please!! Do you have any advice?

yes. read and follow the manuals provided by your distribution (your 
description doesn't sound gentoo-ish, but EVERY distro should have this 
in their documentation).

>
> Thanks,
> Massimiliano
>

Re: [gentoo-user] Network problem with linux server

[Michael Schreckenbauer]

Hi,

Am Montag, 7. November 2011, 12:13:58 schrieb Massimiliano Ziccardi:
> Hi All.
> 
> This problem is not strictly related to gentoo, however I'm sure someone
> here will be able to help me in some way: sorry if I bother you!

have a look at:
http://www.centos.org/docs/5/html/5.1/Deployment_Guide/s1-networkscripts-
static-routes.html

Best,
Michael

Re: [gentoo-user] Network problem with linux server

[Massimiliano Ziccardi]

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Already done.
I asked here because I hoped someone would be able to give me some hint
about why with the routes I sent in the previous e-mail pinging the default
gateway it
pings itself (I verified that pinging every server with address
195.75.145.xxx pings the server itself as if it was a loopback address).

Thanks,
Massimiliano

On Mon, Nov 7, 2011 at 12:52, Michael Schreckenbauer <grimlog@gmx.de> wrote:

> Hi,
>
> Am Montag, 7. November 2011, 12:13:58 schrieb Massimiliano Ziccardi:
> > Hi All.
> >
> > This problem is not strictly related to gentoo, however I'm sure someone
> > here will be able to help me in some way: sorry if I bother you!
>
> have a look at:
> http://www.centos.org/docs/5/html/5.1/Deployment_Guide/s1-networkscripts-
> static-routes.html
>
> Best,
> Michael
>
>
>

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