[SOLVED] Problem in SSHing arch from a different machine

spandan.anupam · 2018-12-26 05:34:48

/dev/zero wrote:

A simple way to test whether an ssh service is actually listening on a remote machine is to use telnet. If you run "telnet 192.168.1.33 22" you should see something like this:
$ telnet 192.168.1.33 22
Trying 192.168.1.33...
Connected to 192.168.1.33.
Escape character is '^]'.
SSH-2.0-OpenSSH_7.9
Notice how the sshd service displays a banner showing its version. (Press '^]' followed by Ctrl-D to terminate the telnet session after checking the banner.)
The benefit of doing this is if you can't even get a telnet banner then you know it is either a network issue or a firewall issue.
Whereas, if telnet shows you the banner for your ssh server, then you know that the network and firewall are okay, and it will be better to focus on the ssh client and sshd service configurations.

spandan@spandan ~ $ telnet 192.168.1.33 22
Trying 192.168.1.33...

It doesn't go any further than this.

ngoonee · 2018-12-26 06:21:52

You have a general network connectivity issue. If I were to guess, it would be that your router is somehow filtering traffic between your wired and wireless. This can happen if the wireless network is configured as a 'guest' network (at least for ASUS routers). Check your router's settings for similar, this is unlikely to be an Arch issue.

spandan.anupam · 2018-12-26 07:20:54

ngoonee wrote:

You have a general network connectivity issue. If I were to guess, it would be that your router is somehow filtering traffic between your wired and wireless. This can happen if the wireless network is configured as a 'guest' network (at least for ASUS routers). Check your router's settings for similar, this is unlikely to be an Arch issue.

Okay then, now it has been boiled down to my router so I should close this thread.

seth · 2018-12-26 08:49:32

Can the macbook actually ping other devices in the 192.168.1.0/24 subnet?
I don't really know what to make out of the OSX route outputs, but this somehow smells like a VPN w/ special handling of the LAN and that somehow fails?

fukawi2 · 2018-12-27 05:33:05

Run the below command on your arch machine, then try and connect from your mac via SSH:

tcpdump -lnnienp2s0 port 22

Post the output for us here.

(Yes, you'll probably have to install tcpdump from the repos)

Last edited by fukawi2 (2018-12-27 05:33:29)

spandan.anupam · 2018-12-28 12:36:03

seth wrote:

Can the macbook actually ping other devices in the 192.168.1.0/24 subnet?
I don't really know what to make out of the OSX route outputs, but this somehow smells like a VPN w/ special handling of the LAN and that somehow fails?

Sorry, I cannot really know anything about that, as I have only these two devices with me. I will try though, but it is very unlikely, and sorry for replying late.

Last edited by spandan.anupam (2018-12-28 12:39:59)

spandan.anupam · 2018-12-28 12:39:27

fukawi2 wrote:

Run the below command on your arch machine, then try and connect from your mac via SSH:
tcpdump -lnnienp2s0 port 22
Post the output for us here.
(Yes, you'll probably have to install tcpdump from the repos)

Sorry for replying late, but my arch machine doesn't do anything from that code. I used -vv too here.

tcpdump: listening on enp2s0, link-type EN10MB (Ethernet), capture size 262144 bytes
^C
0 packets captured
0 packets received by filter
0 packets dropped by kernel

seth · 2018-12-28 15:40:16

tcpdump sniffs the network traffic, so it makes only sense to run this in parallel to attempted ssh connects. The ping failures however make it unlikely that you're getting packages incoming on port 22.
If you've a smartphone or tablet, they'll usually respond to pings as well.

fukawi2 · 2018-12-29 04:32:45

spandan.anupam wrote:

tcpdump: listening on enp2s0, link-type EN10MB (Ethernet), capture size 262144 bytes
^C
0 packets captured
0 packets received by filter
0 packets dropped by kernel

OK, so that shows that the packets are not even reaching your Arch machine (tcpdump will show packets even if they're blocked by the local firewall). There's something funky going on in your network and/or the Mac that is preventing your connection.

Arch Linux

#26 2018-12-26 05:34:48

Re: [SOLVED] Problem in SSHing arch from a different machine

#27 2018-12-26 06:21:52

Re: [SOLVED] Problem in SSHing arch from a different machine

#28 2018-12-26 07:20:54

Re: [SOLVED] Problem in SSHing arch from a different machine

#29 2018-12-26 08:49:32

Re: [SOLVED] Problem in SSHing arch from a different machine

#30 2018-12-27 05:33:05

Re: [SOLVED] Problem in SSHing arch from a different machine

#31 2018-12-28 12:36:03

Re: [SOLVED] Problem in SSHing arch from a different machine

#32 2018-12-28 12:39:27

Re: [SOLVED] Problem in SSHing arch from a different machine

#33 2018-12-28 15:40:16

Re: [SOLVED] Problem in SSHing arch from a different machine

#34 2018-12-29 04:32:45

Re: [SOLVED] Problem in SSHing arch from a different machine

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