Si usamos
export HISTTIMEFORMAT="%d/%m/%y %T "
Obtendríamos un resultado similar a este :
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421 20/04/10 21:10:27 cp -vRf * ../ubuntu
422 20/04/10 21:10:27 cd ..
423 20/04/10 21:10:27 mount
424 20/04/10 21:10:27 umount /var/www/tmp
425 20/04/10 21:10:27 ll
426 20/04/10 21:10:27 cd ubuntu/
427 20/04/10 21:10:27 l
428 20/04/10 21:10:27 cd install/
429 20/04/10 21:10:27 ll
430 20/04/10 21:10:27 cd netboot/
431 20/04/10 21:10:27 ll
432 20/04/10 21:10:27 ll /var/lib/tftpboot/
433 20/04/10 21:10:27 cp -Rf * /var/lib/tftpboot/
434 20/04/10 21:10:27 ll /var/lib/tftpboot/
435 20/04/10 21:10:27 cp -Rf * /var/lib/tftpboot/ubuntu-installer/
436 20/04/10 21:10:27 ll
437 20/04/10 21:10:27 ll ubuntu-installer/
438 20/04/10 21:10:27 cd /var/lib/tftpboot/
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Para hacer los cambios permanentes puede añadirse el comando anterior en tu .bashrc
echo 'export HISTTIMEFORMAT="%d/%m/%y %T "' | tee -a ~/.bashrc