wiki:telehouse_serial_access

Version 49 (modified by Jamie McClelland, 9 years ago) (diff)

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How do I connect to an MF/PL server located at Telehouse via the serial port?

Note: if you are trying to connect to a server in our XO/Bandcon, see our XO serial access page; for Sunset Park see Sunset Park serial acess page.

Serial Console physical setup

In the MF/PL Telehouse rack, we have two 8 port USB to serial adapters using the pl2303 chipset robideau.

  • In:
    • First USB device
      • kiyoshi (Cable 1, sylvia: ttyUSB0)
      • NOT IN USE (Cable 2, sylvia: ttyUSB1)
      • NOT IN USE (Cable 3, sylvia: ttyUSB2)
      • gramsci (Cable 4, sylvia: ttyUSB3)
      • sontag (Cable 5, sylvia: ttyUSB4)
      • menchu (Cable 6, sylvia: ttyUSB5)
      • hubert (Cable 7, sylvia: ttyUSB6)
      • gabriel (Cable 8, sylvia: ttyUSB7)
    • Second USB device
      • shadow (Cable 1, sylvia: ttyUSB8)
      • goofball (Cable 2 sylvia: ttyUSB9)
      • tenant (Cable 3 sylvia: ttyUSB10)
      • karl (Cable 4 sylvia: ttyUSB11)
      • NOT IN USE (Cable 5 sylvia: ttyUSB12)
      • bolivar (Cable 6 sylvia: ttyUSB13)
      • NOT IN USE (Cable 7 sylvia: ttyUSB14)
      • fred (Cable 8 sylvia: ttyUSB15)

The serial consoles of the attached machines are all remotely accessible (to properly-authenticated people), and they are also logged and timestamped. We are using cereal to do this cleanly and easily.

How to connect

In order to connect via serial console to one of the servers named above, ssh into console.mayfirst.org as servername-console

For example:

ssh -t ken-console@console.mayfirst.org cereal attach ken 

Would give you full read/write access to the console on ken.

The SSH RSA host key for console.mayfirst.org should have a fingerprint of:

2048 76:6d:60:7e:de:5e:87:70:1f:27:d8:53:03:83:2c:f5 console.mayfirst.org,209.51.172.10

We can also setup additional users that have read-only access to the sessions created by each of these usernames, should that be desirable. You can request such access by creating a ticket.

In addition - we have a serial line running from bolivar's /dev/ttyUSB0 that goes to robideau's built-in serial port 1, so that robideau's console itself is remotely accessible, and logged. You can connect to robideau's console with:

ssh -t robideau-console@bolivar.mayfirst.org cereal attach robideau 

Setting up a new console user

To setup a new console user (this is something only admins can do), do the following as root@sylvia:

adduser --disabled-password --gecos='fred console user,,,' fred-console
cereal-admin create fred /dev/ttyS15 115200 fred-console fred-console
cereal-admin start fred