Network scripts question -

[Bob Goodwin]

I have two F-15 computers. Box6 has the following files while box9
    has only /etc/sysconfig/network-scripts/ifcfg-lo, both are using
    NetworkManager.

[bobg@box6 ~]$ ll /etc/sysconfig/network-scripts/ifcfg-*

-rw-r--r--. 3 root root 577 Jun 22 18:16
        /etc/sysconfig/network-scripts/ifcfg-eth1
        -rw-r--r--. 1 root root 254 Apr 27 13:17
        /etc/sysconfig/network-scripts/ifcfg-lo
        -rw-r--r--. 3 root root 577 Jun 22 18:16
        /etc/sysconfig/network-scripts/ifcfg-p2p1

I can ssh from box6 to box9 but not from box9 to box6. Either one
    will ping the other, stopping the fire wall does not have any effect.

Any suggestions, what to look for?

Bob
    .--

[Aaron Konstam]

On Sun, 2011-07-31 at 15:36 -0400, Bob Goodwin wrote:
> I have two F-15 computers. Box6 has the following files while box9
>     has only /etc/sysconfig/network-scripts/ifcfg-lo, both are using
>     NetworkManager.
>     [bobg@box6 ~]$ ll /etc/sysconfig/network-scripts/ifcfg-*
>
>     -rw-r--r--. 3 root root 577 Jun 22 18:16
>     /etc/sysconfig/network-scripts/ifcfg-eth1
>     -rw-r--r--. 1 root root 254 Apr 27 13:17
>     /etc/sysconfig/network-scripts/ifcfg-lo
>     -rw-r--r--. 3 root root 577 Jun 22 18:16
>     /etc/sysconfig/network-scripts/ifcfg-p2p1
>
> I can ssh from box6 to box9 but not from box9 to box6. Either one
> will ping the other, stopping the fire wall does not have any effect.
>
> Any suggestions, what to look for?
>
> Bob
> .--

The ifcfg-lo is for local self-conection so it is understandable that
box9 can't reach box6.

You will have to create ifcfg-eth1  if you have a wired connection.
Mine looks something like this:
DEVICE="eth1"
HWADDR="00:14:22:2A:3B:FE"
BOOTPROTO="dhcp"
ONBOOT="yes"
NM_CONTROLLED="yes"

system-config-network might aid you in this file creation.

[Bob Goodwin]

On 31/07/11 17:25, Aaron Konstam wrote:
> On Sun, 2011-07-31 at 15:36 -0400, Bob Goodwin wrote:
> > I have two F-15 computers. Box6 has the following files while box9
> >      has only /etc/sysconfig/network-scripts/ifcfg-lo, both are using
> >      NetworkManager.
> >      [bobg@box6 ~]$ ll /etc/sysconfig/network-scripts/ifcfg-*
> >
> >      -rw-r--r--. 3 root root 577 Jun 22 18:16
> >      /etc/sysconfig/network-scripts/ifcfg-eth1
> >      -rw-r--r--. 1 root root 254 Apr 27 13:17
> >      /etc/sysconfig/network-scripts/ifcfg-lo
> >      -rw-r--r--. 3 root root 577 Jun 22 18:16
> >      /etc/sysconfig/network-scripts/ifcfg-p2p1
> >
> >  I can ssh from box6 to box9 but not from box9 to box6. Either one
> >  will ping the other, stopping the fire wall does not have any effect.
> >
> >  Any suggestions, what to look for?
> >
> >  Bob
> >  .--
>
> The ifcfg-lo is for local self-conection so it is understandable that
> box9 can't reach box6.
>
> You will have to create ifcfg-eth1  if you have a wired connection.
> Mine looks something like this:
> DEVICE="eth1"
> HWADDR="00:14:22:2A:3B:FE"
> BOOTPROTO="dhcp"
> ONBOOT="yes"
> NM_CONTROLLED="yes"
>
> system-config-network might aid you in this file creation.

I thought adding it might be the solution but I don't recall
        adding it to this F-15 computer?

And system-config-network wont let me do anything but enter DNS
        information?
        I'll add the missing file and see what the result is.

Thanks,

Bob

[Tom H]

On Sun, Jul 31, 2011 at 5:25 PM, Aaron Konstam  wrote:
> On Sun, 2011-07-31 at 15:36 -0400, Bob Goodwin wrote:
> > I have two F-15 computers. Box6 has the following files while box9
> > has only /etc/sysconfig/network-scripts/ifcfg-lo, both are using
> > NetworkManager.
> >
> > [bobg@box6 ~]$ ll /etc/sysconfig/network-scripts/ifcfg-*
> >
> > -rw-r--r--. 3 root root 577 Jun 22 18:16
> >         /etc/sysconfig/network-scripts/ifcfg-eth1
> >         -rw-r--r--. 1 root root 254 Apr 27 13:17
> >         /etc/sysconfig/network-scripts/ifcfg-lo
> >         -rw-r--r--. 3 root root 577 Jun 22 18:16
> >         /etc/sysconfig/network-scripts/ifcfg-p2p1
> >
> > I can ssh from box6 to box9 but not from box9 to box6. Either one
> >     will ping the other, stopping the fire wall does not have any effect.
>
> The ifcfg-lo is for local self-conection so it is understandable that
> box9 can't reach box6.
>
> You will have to create ifcfg-eth1  if you have a wired connection.
> Mine looks something like this:
> DEVICE="eth1"
> HWADDR="00:14:22:2A:3B:FE"
> BOOTPROTO="dhcp"
> ONBOOT="yes"
> NM_CONTROLLED="yes"

I have one VM on my laptop and two dev boxes - all serving out sshd,
nfsd, and smbd - on which NM's running with only an ifcfg-lo file.

Furthermore, since the boxes can ping each other and there's one-way
ssh access, the presence/absence of an ifcfg-* file isn't issue.

I'd focus on troubleshooting sshd on box6.

[Bob Goodwin]

On 31/07/11 20:29, Tom H wrote:
> I have one VM on my laptop and two dev boxes - all serving out sshd,
> nfsd, and smbd - on which NM's running with only an ifcfg-lo file.
>
> Furthermore, since the boxes can ping each other and there's one-way
> ssh access, the presence/absence of an ifcfg-* file isn't issue.
>
> I'd focus on troubleshooting sshd on box6.

I'm not sure how to troubleshoot ssh. The path between the two
    computers is wired, through a Netgear gigabit switch which also
    connects the NFS server, a printer, and the wireless access device.
    The ethernet stuff all seems to work. I've been considering
    switching ports around to get box 6 on a different port ... If it's
    the switch I will have to get another one since I need all the
    ports. Box6 has a gigabit NIC, I could try the slower port on the
    motherboard. But that's assuming a hardware problem which seems
    improbable, though possible.

Thoughts and suggestions appreciated.

Bob

[Timothy Murphy]

Bob Goodwin wrote:
> I'm not sure how to troubleshoot ssh.

ssh -v ...
might give you some information.

[Adalbert Prokop]

Am 31.07.2011 21:36, schrieb Bob Goodwin:

Hi Bob!
> I can ssh from box6 to box9 but not from box9 to box6. Either one
> will ping the other, stopping the fire wall does not have any effect.

- Is ssh on box6 running? (# service sshd status)
- On which port? (look in /etc/ssh/sshd_config)
- To which host:port are you connecting using ssh from box9 to box6?
  (box9# ssh -v box6)
- Does the ssh daemon receive the connection on box6? (monitor logs
  in (/var/log/messages)
- Does the firewall on box6 allow SSH connections?
  (iptables -L -n -v INPUT)
- Who resolves box6 into an IP number, i.e. who is the DNS server? Does
  the connection work if you use IPs instead of names directly?

[Bob Goodwin]

On 07/08/11 02:09, Adalbert Prokop wrote:
> Am 31.07.2011 21:36, schrieb Bob Goodwin:
>
> Hi Bob!
> >  I can ssh from box6 to box9 but not from box9 to box6. Either one
> >  will ping the other, stopping the fire wall does not have any effect.
> Is ssh on box6 running? (# service sshd status)
> On which port? (look in /etc/ssh/sshd_config)
> To which host:port are you connecting using ssh from box9 to box6?
>  (box9# ssh -v box6)
> Does the ssh daemon receive the connection on box6? (monitor logs
>  in (/var/log/messages)
> Does the firewall on box6 allow SSH connections?
>  (iptables -L -n -v INPUT)
> Who resolves box6 into an IP number, i.e. who is the DNS server? Does
>  the connection work if you use IPs instead of names directly?

Adalbert:

I just began checking as you suggest only to find that ssh is
        working normally this morning! It did not work when I needed it
        and as a result I lost all my Thunderbird mail files attempting
        to work around the problem. Result much inconvenience and extra
        work! However here we are a week later and it's working as it
        should? I even tried different ethernet cables, different ports
        on the ethernet switch, everything I could think of to no avail ...

Thank you for delineating a test procedure. I have copied it
        into my Linux notes and will do as you suggest if/when the
        problem reoccurs.

Thank you.

Bob