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Old 03-02-2016, 06:19 PM   #1
amiba
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Smile ssh tunnel to localhost is on the remote host not comming from 127.0.0.1


I've lot's of servers running in the net and one of them is very special. They all run ubuntu. In this case 14.4.

I got the following problem. Normal if I do need to do some support for anyone, I do an ssh tunnel to the system and use x11vnc to connect over ssvnc with the system to watch what the customer tries to do and tell him how ot get it working.

So it was working all the time fine and in my .x11vncrc I've got ever localhost, as I don't want someone to connect to the unit from outside in the net and put in passwords, maybe without any encryption.

two weeks ago I did upgrade the unit with apt-get update && apt-get upgrade and everythin seams to work fine there. But next time I went on the system I could not start the session ssvnc becaus it was been not accepted as the request was not comming from 127.0.0.1 it was comming from the servers own 192.168.xxx.xxx Adress. So I don't know how this could happened. I've not a problem to get on as I am able to modify the .x11vncrc on the remote system.
But I want to know how and where I have to search to find that fault and if, how I may solve it.
Bei allen anderen Servern verhält sich das normal und der Zugriff kommt von 127.0.0.1

Best regards

Andreas
 
Old 03-03-2016, 04:49 AM   #2
business_kid
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On the misbehaving machine post the output of
Code:
ifconfig -v
cat /etc/hosts
 
Old 03-04-2016, 02:17 PM   #3
amiba
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my settings

here the ifconfig -v output: ifconfig_v.txt
and the /etc/hosts: etc_hosts.txt

Hope it works with this upload function, as I did first get a fault msg. Because they use IBM DOS notation for the filenames.

But shouldn't this files not change with apt-get update and apt-get upgrade?

because I did nothing else to the machine.
Attached Files
File Type: txt ifconfig_v.txt (1.6 KB, 13 views)
File Type: txt etc_hosts.txt (222 Bytes, 9 views)
 
Old 03-05-2016, 11:12 AM   #4
business_kid
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The ifconfig output looks ok.
/etc/hosts I am susoicious of. What is 127.0.1.1 used for?
Do you need all that ipv6 stuff there? Is it there in other machines?
What IP is setup in ssvnc, & x11vnc if any?
 
Old 03-06-2016, 12:06 AM   #5
amiba
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Smile

normaly in x11vnc is localhost activ.

But in this case I hat to #localhost as it wasn't working what is my concern to ask for this. Because If I am looking the incomming of my ssvnc I get the information that the ssvnc comes from 192.168.2.201 what is this pc but not localhost and that is crazy as I am comming cross a long distanc throu a ssh tunnel.

I do ssvnc to localhost on my pc. It should go throu the tunnel -L 5900:127.0.0.1:5900 - I am able to see that it is comming to the remote pc but the remote server does tell from its x11vnc that the call comes from 192.168.2.201 and this is normaly not allowed as I use the switch localhost. So if I want to come on the system I do need to switch that of to get connected. But I don't like this and I don't know how this could be only after apt-get update and upgrade.
 
Old 03-07-2016, 05:42 AM   #6
business_kid
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You have several boxes set up this way, all running Ubuntu. Only one misbehaves.

Have you compared the configs? If not why not?

Is that the only box you updated? Or are the others up to date?
 
Old 03-08-2016, 03:03 AM   #7
amiba
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Smile I did search for a different adjustment - can't find it.

The only different thing on this Box is, that it is switched each day of and that it contains no raid5 because it is more used as a Remote PC.
Maybe it is one of the older once. I may remember that I could not use the killer ethernet controller at the very first days of this unit. But I could manage that. All boxes has got the nearly same Motherboard and are made as storage devices.

But the part of x11vnc is precise the same. I've sometimes a different port for ssh but this shouldn't matter that way.
Not all of them are up to date, but some and they work fine.

I tried this week a test for upgrading one of them to make sure, this isn't the cause.

Last edited by amiba; 03-08-2016 at 03:05 AM.
 
Old 03-09-2016, 05:36 AM   #8
business_kid
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Have you experimented with pinging (& ping6-ing) localhost and 127.0.0.1?
 
  


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