Changes between Version 79 and Version 80 of telehouse_serial_access

Timestamp:

Feb 15, 2018, 10:05:50 PM (8 years ago)

Author:

Jamie McClelland

Comment:

--

telehouse_serial_access

@@ -7 +7 @@
 == Serial Console physical setup ==
 
-In the MF/PL Telehouse rack, we have two startech 16-port USB to serial adapters using the FTDI chipset connected to the server `robideau`. These need to be connected to the front USB ports  [ticket:6304 for some reason we do not yet understand] 
+In the MF/PL Telehouse rack, we have two startech 16-port USB to serial adapters using the FTDI chipset connected to the server `robideau`. 
 
 Run:
@@ -17 +17 @@
 To see the layout.
 
-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 [http://cmrg.fithhorseman.net/wiki/cereal cereal] to do this cleanly and easily.
+The serial consoles of the attached machines are all remotely accessible (to properly-authenticated people), and they are also logged and time-stamped.  We are using [http://cmrg.fithhorseman.net/wiki/cereal cereal] to do this cleanly and easily.
 
 == How to connect ==
@@ -46 +46 @@
 == Setting up a new console user ==
 
-To setup a new console user (this is something only admins can do), do the following as `root@robideau`:
+=== Overview ===
+
+To ensure the proper device is connected to the proper path on reboots, we maintain a udev configuration here:
+
+/etc/udev/rules.d/z25_persistent_usb_serial.rules
+
+A sample entry is:
+
+{{{
+SUBSYSTEMS=="usb", ENV{ID_SERIAL}=="FTDI_FT232R_USB_UART_ST161539",SYMLINK+="ttyUSBmalaka"
+}}}
+
+This means, create a symlink called /dev/ttyUSBmalaka for the device with the serial number "FTDI_FT232R_USB_UART_ST161539"
+
+The first step is to figure out which serial number is used by the cable you are using.
+
+The second step is to create the right rule the creates a consistent symlink based on that serial number.
+
+The third step is to create a cereal-admin entry pointing to the symlink.
+
+=== Actual steps ===
+
+First, plug your server or device into an un-used port on one of our USB serial adapters.
+
+Second, as root run `cereal-admin list` and note all the cereal instance named "test." These are the un-allocated ones.
+
+Next, login with the username `pdu-console@console.mayfirst.org`. This user has access to all the un-allocated cereal instances. 
+
+As `pdu-console`, run `cereal attach <instance>` (replace instance with test0, test4, etc.). Run through all the available instances until you find yours.
+
+When you find yours, figure out the mapping. test0 is connected to /dev/ttyUSB0, test4 is /dev/ttyUSB4, etc. Run: `ls -l /dev/serial/by-id/` and figure out which id is pointing to the device that is yours.
+
+Then, edit `/etc/udev/rules.d/z25_persistent_usb_serial.rules` - adding a line with your id and a human name.
+
+Restart udev and re-trigger creation of symlinks with `systemctl restart udev && udevadm trigger -s tty`.
+
+Lasly, to setup a new console user (this is something only admins can do), do the following as `root@robideau`:
 
 {{{
 adduser --disabled-password --gecos='fred console user,,,' fred-console
-cereal-admin create fred /dev/ttyUSB8 115200 fred-console fred-console
+cereal-admin create fred /dev/ttyUSBfred 115200 fred-console fred-console
 cereal-admin start fred
 }}}