FAQ: Why does SecureCRT fail to log commands or other data I can see on the screen?
What is the problem?
You're using SecureCRT to connect to an HP Aruba network device (or similar) and you have logging enabled. You can see the lines of information that you type in the terminal screen, but those lines are not included in the log file.
Why might this be happening?
In order to eliminate superfluous data from appearing in the log file (like when you mistype a command and have to backspace to correct it), SecureCRT writes data to the log file only when the end of the current line has been reached – in other words, when a CR or LF character is received. Once a CR or an LF character is received, SecureCRT takes the visible text on the current line and writes it to the log file.
Some remote hosts, such as HP Procurve and Aruba switches, don’t follow basic terminal norms in which a "line" is terminated with a CR or LF. When you press [Enter] to submit a command when connected to such devices, the device does not send SecureCRT any line termination character (a CR or an LF); rather, it sends SecureCRT a sequence of cursor movement codes that cannot be interpreted in a general case as being an "end of line marker". Since there is no CR or LF character received for that line on which a command has been typed -- and because the cursor has now been moved to another line -- the line with the command won't get logged by SecureCRT.
This is an image of the raw log of all of the escape sequences that were sent to SecureCRT by a particular Aruba device after [Enter] was pressed to complete a command:
A raw log captures *all* characters received from a connected device. You can see that the device doesn't send any CR or LF when a command is echo'd back to SecureCRT.
You can also see for such devices how absolutely unreadable a raw log is because of all the extraneous escape sequences these devices send whenever any character is typed into the terminal.
What’s the solution? In what SecureCRT version is the solution available?
A new INI-file-only session option was added as of SecureCRT version 8.7, called Log Screen. This option allows all data displayed in the terminal to be logged at the time it appears on screen, as opposed to when a CR or LF is received by SecureCRT.
From within a script
What caveats are there?
This Log Screen option will log everything that is sent to SecureCRT’s terminal screen. This includes redraws that are caused by backspaces or tab completions, which means that generally, the log file’s going to show some interesting things. For example, if you used tab completion and backspace to correct some errors a couple times while typing in the following command:
show ip route connected... in the log file you might see something like this:
Aruba-1# shiAruba-1# shoAruba-1# show ip royAruba-1# show ip rouAruba-1# show ip route connAruba-1# show ip route connectedFor each backspace or tab completion, the device actually re-draws the entire line; and these re-draw occurrences will show up in the log file because SecureCRT is now logging every character that is ever displayed on the screen.
Last edited by jdev; 12-02-2020 at 07:33 AM.
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