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When using RealPort in Linux, the device permission settings applied with dgrp_gui or dgrp_cfg_node do not stay after rebooting

Most newer Linux distribution versions and kernels now use UDEV for device creation. When using UDEV all permissions are now set by UDEV, the driver dgrp_gui/dgrp_cfg_node permission settings no longer control these settings on newer kernels/distributions.

When using UDEV, you can modify the permissions by modifying the RealPort UDEV script, called "10-dgrp.rules" in /etc/udev/rules.d.

Here are the default entries found in /etc/udev/rules.d/10-dgrp.rules:

KERNEL="tty_dgrp*", PROGRAM="/usr/bin/dgrp_udev %k", NAME="%c" KERNEL="cu_dgrp*", PROGRAM="/usr/bin/dgrp_udev %k", NAME="%c" KERNEL="pr_dgrp*", PROGRAM="/usr/bin/dgrp_udev %k", NAME="%c"

The cu_dgrp devices have been deprecated for several years in Linux and are not used. Placing a hash (#) in front of this line will prevent the device creation.

The pr_dgrp devices are used for transparent/pass through printing. This is where there is a printer attached to the printer port of a terminal or PC using a tty device.

To change the UDEV rule syntax on the tty_dgrp* devices to set 666 permissions (typically used for getty):

# this will set all digi dgrp ttys KERNEL=="tty_dgrp*", PROGRAM="/usr/bin/dgrp_udev %k", NAME="%c", GROUP="root", MODE="0666", OPTIONS="last_rule"

Example for configuring printer devices on specific ports:

# set ttyaa10-ttyaa15 ports (jacks 11-16) for printers
KERNEL=="tty_dgrp_aa_1[0-5]*", PROGRAM="/usr/bin/dgrp_udev %k", NAME="%c", GROUP="lp", MODE="0666", OPTIONS="last_rule"

When using a wildcard rule (i.e.: "tty_dgrp*"), you will need to place that rule below rules setting specific ports. For example:

# set ttyaa10-ttyaa15 ports (jacks 11-16) for printers KERNEL=="tty_dgrp_aa_1[0-5]*", PROGRAM="/usr/bin/dgrp_udev %k", NAME="%c", GROUP="lp", MODE="0666", OPTIONS="last_rule" # this will set all digi dgrp ttys KERNEL=="tty_dgrp*", PROGRAM="/usr/bin/dgrp_udev %k", NAME="%c", GROUP="root", MODE="0666", OPTIONS="last_rule"

Test the permissions:

1) Run "udevcontrol reload_rules"

2) /etc/init.d/dgrp_daemon restart

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