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7. How do I do this or find out that ... ?

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7.1 How can I get scrollback in text mode?

With the default US keymap you can use Shift with the PageUp and PageDown keys (NB: these must be the grey ones, not the ones on the numeric keypad!). With other keymaps check the maps in /usr/lib/keytables; you can remap the ScrollUp and ScrollDown keys to be whatever you like -- for example, in order to remap them to keys that exist on an 84-key AT keyboard.

You can't increase the amount of scrollback, because of the way it is implemented using the video memory to store the scrollback text, though you may be able to get more scrollback in each virtual console by reducing the total number of VC's -- see <linux/tty.h>.

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7.2 How do I switch virtual consoles? How do I enable them?

In text mode, press Left Alt-F1 to Alt-F12 to select the consoles tty1 to tty12; Right Alt-F1 gives tty13 and so on. To switch out of X windows you must press Ctrl-Alt-F1, etc; Alt-F5 or whatever will switch back.

If you want to use a VC for ordinary login you need to list it in /etc/inittab, which controls which terminals and virtual consoles have login prompts. NB: X needs at least one free VC in order to start.

Kernels earlier than around 1.1.59 have a compiled-in limit on the number of consoles, for which the default is 8. See NR_CONSOLES in linux/include/linux/tty.h. Newer kernels allocate them dynamically, up to a maximum of 63.

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7.3 How do I set the timezone?

Change directory to /usr/lib/zoneinfo; get the timezone package if you don't have this directory. The source is available as sunsite.unc.edu/pub/Linux/system/admin/time/timesrc-1.2.tar.gz.

Then make a symbolic link named localtime pointing to one of the files in this directory (or a subdirectory), and one called posixrules pointing to localtime. For example:

   ln -sf US/Mountain localtime
   ln -sf localtime posixrules
This change will take effect immediately -- try date(1).

Don't try to use the TZ variable -- leave it unset.

You should also make sure that your Linux kernel clock is set to the correct GMT time -- type date -u and check that the correct universal time is displayed.

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7.4 What version of Linux and what machine name am I using?

Type:

   uname -a

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7.5 How can I enable or disable core dumps?

Linux now has corefiles turned off by default for all processes.

You can turn them on or off by using the ulimit(1)