Serial console not working on Ubuntu 10.10

[Gaurav Aggarwal]

I am trying to setup a serial console between two ubuntu machines. Basically, I am trying to follow the below mentioned article for the same, but with no luck so far.

https://help.ubuntu.com/community/SerialConsoleHowto

I am pretty sure that my server side configurations are done properly since I am getting the login prompt when using windows machine (hyperterminal) as client to connect any of these machines. But, when I am trying to connect to the same machine from another Ubuntu machine (via minicom) as the client, I am not getting the login prompt on the serial console.

Since setup is working fine with the windows (hyperterminal). On looking further, I found that similar settings are working fine with the Cent OS, so this rules out any minicom related setting issue also. So, I guess, there is a bug in the Ubuntu distribution.

[Gaurav Aggarwal (gaurav.aggarwal)]

Kernel running on the client machine is 2.6.35-22

[Dave Walker (davewalker)]

Hi Gaurav,

At which point is serial console not working for you? Is this from Grub, or plain console over serial?

If it's the first, the section "Configuring upstart (Karmic and newer)" followed by the two steps does produce a working serial console for me.

Can you reproduce this using screen as an alternative to minicom:
on the client run, "$ screen /dev/ttyS0 115200" (you may require sudo).

Thanks.

[Gaurav Aggarwal (gaurav.aggarwal)]

Hi Dave,

Its the second step , getting the plan console (prompt) over the serial.
Screen command is also not working neither the picocom. Screen command flashes an error, something like, ioctl() command failed.

Some more info:
 If after connecting with the minicom, I restarted the other machine (on which serial console is connected), I do see the logout and boot messages on my minicom screen but output is not formatted properly. It looks like this:

  [ 0.332483] pci 0000:00:1d.7: PME# supported from D0 D3hot D3cold

                                                                                 [ 0.336007] pci 0000:00:1d.7: PME# disabled

                                                                                                                               [ 0.340057] * The chipset may have PM-
Timer Bug. Due to workarounds for a bug, +-------------------+
                                                                          | |
                                        [ 0.340059] * this clock source| Resetting Modem |sure your timer does not have
                                                                          | |
                                                                          +-------------------+ [ 0.340060] * this bug, please use "acpi_
pm_good" to disable the workaround

In some cases, these messages stop coming after some time and in other case, I got the login prompt, but then it is not taking any input from my machine's keyboard for that minicom session. Moreover, the behavior is not consistent.

Also, note that if I give a command like:
echo "testing" > /dev/ttyS0
to the machine on which serial console is connected, I can see the output "testing" in other machine's minicom session (but again data is not properly formatted)

Please let me know if you need any other information from my side regarding the same.

[Scott Moser (smoser)]

I'm sorry to ask another question, but could you please clarify ? From my reading, it appears that you are attempting to connect via serial cable and minicom 2 machines of 10.10. Your problem is that when looking at output in minicom, the text isn't aligned/wrapped correctly. Is that right ?

[Gaurav Aggarwal (gaurav.aggarwal)]

Scott, your statement is partially correct. You are right in understanding that I am trying to connect two Ubuntu 10.10 machines via serial console. In doing so, I am facing two problems mainly:
- I am not able to write username/password (or any other input) using minicom/screen as a client
- Output (boot messages and other text) isn't aligned properly (even when linewrap is enabled)
Let me know, if you need any other information from my side regarding the same.

[Clint Byrum (clint-fewbar)]

Gaurav, its been a long time since there has been any activity on this bug. Meanwhile Ubuntu 10.10 has reached its end of life. I wonder if its worth keeping the report open, since there have been no other bugs reported like this, and Dave Walker was able to setup a serial console using the same instructions.

I'm going to mark as Incomplete. If we don't hear from you in 60 days, we'll close this bug report.

Thanks for your time.

[Launchpad Janitor (janitor)]

[Expired for minicom (Ubuntu) because there has been no activity for 60 days.]