Guralp Systems CMG-DCM build <10,000 User Manual
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Acquisition Modules and Platinum Firmware
Recording and Retrieving Data
A typical invocation looks like this:
eam999# Pt-storage-adduser dskusr
New password:
Repeat password:
Password changed
New user 'dskusr' added and ready
eam999#
The chosen username, “dskusr” in this example, can be anything you wish
but must consist of lower-case letters and digits only.
The new user can now be used with file transfer commands. For example,
from a Linux box, you could enter commands like
me@mypc:~/dl $ ssh dskusr@eam999 gdi-record --flush
me@mypc:~/dl $ rsync -avz dskusr@eam999:/media/*/
This will flush outstanding data from the ring-buffers and then synchronise
all files from the mass storage device to the current directory on the invoking
computer.
It is also possible to eliminate the password prompt. To do this:
•
Run the following commands on the Platinum system:
mkdir -m 700 ~dskusr/.ssh > ~dskusr/.ssh/authorized_keys
chmod 600 ~dskusr/.ssh/authorized_keys
replacing dskusr with the name of your own special user.
•
create an ssh key pair on the client PC, using the sshkeygen
command on Linux or the PuTTYgen application on windows.
•
Copy the newly created public key into the authorized_keys file.
The new user should now be able to invoke ssh, scp, sftp or rsync without
being prompted for a password.
Once you are happy that password-less logins are working, you can remove
the password for the new user by editing /etc/shadow on the Platinum
system and replacing the encrypted password – the part of the line between
the first and second colons – with an exclamation mark ('!').
11.3.1.4 Downloading over a serial port, using the command line
In situations where it is not convenient to use the network interface, files can
be downloaded from the removable mass storage device using one of three
file-transfer protocols, X-modem, Y-modem or Z-modem. None of these
protocols were ever rigidly standardised so, if you are not using one of the
terminal emulators discussed in this section, you may need to experiment a
little: this is reflected in the huge range of optional arguments that the transfer
program accepts.
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Issue E - February 2014