Locking USB Serial Device to Specific Com port

[dweimer]

I have two USB Serial adapters I use on my web server, ones always
connected, to allow NUT to monitor my UPS. The other I use to view the
console of my pfSense firewall, however I sometimes disconnect this one
to use it with my laptop to configure switches.

Because this one is unplugged and plugged back in, sometimes on reboot
it ends up switching its com port with the UPS, so NUT fails to start
and the UPS is unmonitored.

I would like to lock down the USB serial port adapter used on the UPS
to /dev/cuaU0, to make sure the UPS is always monitored and I will get a
clean shutdown in event of a power failure.

I believe that this requires setting a hint line of some sort in the
/boot/loader.conf file, but I am having trouble tracking down what this
should be, or maybe I am on the wrong track. Here is the current
information from the adpapters, the UPS adapter was connected at boot,
is on /dev/cuaU0, the other one was plugged in after boot, and is on
/dev/cuaU1.


dmesg output:
ugen0.2: <Prolific Technology Inc.> at usbus0
uplcom0: <Prolific Technology Inc. USB-Serial Controller, class 0/0,
rev 1.10/3.00, addr 2> on usbus0
ugen0.3: <Prolific Technology Inc.> at usbus0
uplcom1: <Prolific Technology Inc. USB-Serial Controller, class 0/0,
rev 1.10/3.00, addr 3> on usbus0

sysctl -a | grep uplmon:
device uplcom
hw.usb.uplcom.debug: 0
dev.uplcom.0.%desc: Prolific Technology Inc. USB-Serial Controller,
class 0/0, rev 1.10/3.00, addr 2
dev.uplcom.0.%driver: uplcom
dev.uplcom.0.%location: bus=1 hubaddr=3 port=0 devaddr=2 interface=0
dev.uplcom.0.%pnpinfo: vendor=0x067b product=0x2303 devclass=0x00
devsubclass=0x00 sernum="" release=0x0300 mode=host intclass=0xff
intsubclass=0x00 intprotocol=0x00 ttyname=U0 ttyports=1
dev.uplcom.0.%parent: uhub0
dev.uplcom.0.ttyname: U0
dev.uplcom.0.ttyports: 1
dev.uplcom.1.%desc: Prolific Technology Inc. USB-Serial Controller,
class 0/0, rev 1.10/3.00, addr 3
dev.uplcom.1.%driver: uplcom
dev.uplcom.1.%location: bus=1 hubaddr=1 port=0 devaddr=3 interface=0
dev.uplcom.1.%pnpinfo: vendor=0x067b product=0x2303 devclass=0x00
devsubclass=0x00 sernum="" release=0x0300 mode=host intclass=0xff
intsubclass=0x00 intprotocol=0x00 ttyname=U1 ttyports=1
dev.uplcom.1.%parent: uhub0
dev.uplcom.1.ttyname: U1
dev.uplcom.1.ttyports: 1

Does anyone have any suggestions on how to do this?

[Shane Ambler]

I would like to lock down the USB serial port adapter used on the UPS to
/dev/cuaU0, to make sure the UPS is always monitored and I will get a
clean shutdown in event of a power failure.
I believe that this requires setting a hint line of some sort in the
/boot/loader.conf file, but I am having trouble tracking down what this
should be, or maybe I am on the wrong track. Here is the current
information from the adpapters, the UPS adapter was connected at boot,
is on /dev/cuaU0, the other one was plugged in after boot, and is on
/dev/cuaU1.

start with man devd.conf

You can add your own devd files in /usr/local/etc/devd/
Something along the lines of -

attach 200 {
device-name "cuaU[0-9]+";
match "vendor" "0x067b";
match "product" "0x2303";
action "sleep 2; cd /dev; ln -s ${device-name} upsmonitor";
};

use usbconfig to get info. I am thinking with the similarity of the two
you may need to rely on bus and hubaddr or devaddr to keep each device
identified by usb port location.

[dweimer]

Post by Shane Ambler

I would like to lock down the USB serial port adapter used on the UPS to
/dev/cuaU0, to make sure the UPS is always monitored and I will get a
clean shutdown in event of a power failure.
I believe that this requires setting a hint line of some sort in the
/boot/loader.conf file, but I am having trouble tracking down what this
should be, or maybe I am on the wrong track. Here is the current
information from the adpapters, the UPS adapter was connected at boot,
is on /dev/cuaU0, the other one was plugged in after boot, and is on
/dev/cuaU1.

start with man devd.conf
You can add your own devd files in /usr/local/etc/devd/
Something along the lines of -
attach 200 {
device-name "cuaU[0-9]+";
match "vendor" "0x067b";
match "product" "0x2303";
action "sleep 2; cd /dev; ln -s ${device-name} upsmonitor";
};
use usbconfig to get info. I am thinking with the similarity of the two
you may need to rely on bus and hubaddr or devaddr to keep each device
identified by usb port location.

OK, so I was looking in the wrong direction, which might explain why my
searching wasn't finding anything.

However I might still be out of luck, after doing some checking, and a
reboot the only difference I can find is below.

dev.uplcom.0.%location: bus=1 hubaddr=1 port=0 devaddr=2 interface=0
dev.uplcom.1.%location: bus=1 hubaddr=3 port=0 devaddr=3 interface=0

The devices have switch at this point, all info from usbconfig, dmesg,
looks identical, these two lines from the sysctl -a | grep "uplcom"
output is all that changed, the hubaddr=1 and hubaddr=3 have switched,
however the man devd.conf has a variable list, to use, and doesn't seem
to have an option to match agains that hubaddr variable.

Variable Description
bus Device name of parent bus.
cdev Device node path if one is created by the devfs(5)
filesys-
tem.
cisproduct CIS-product.
cisvendor CIS-vendor.
class Device class.
device Device ID.
devclass Device Class (USB)
devsubclass Device Sub-class (USB)
device-name Name of attached/detached device.
endpoints Endpoint count (USB)
function Card functions.
interface Interface ID (USB)
intclass Interface Class (USB)
intprotocol Interface Protocol (USB)
intsubclass Interface Sub-class (USB)
manufacturer Manufacturer ID (pccard).
mode Peripheral mode (USB)
notify Match the value of the ``notify'' variable.
parent Parent device
port Hub port number (USB)
product Product ID (pccard/USB).
release Hardware revision (USB)
sernum Serial Number (USB).
slot Card slot.
subvendor Sub-vendor ID.
subdevice Sub-device ID.
subsystem Matches a subsystem of a system, see below.
system Matches a system type, see below.
type Type of notification, see below.
vendor Vendor ID.


But the action line above does give me an idea though, I should be able
to write a script to run at startup to find the line, and create the
link to the device. The only one I care about is the UPS monitor, as
the other is only occasionally used, and I can easily check which com
port its on before connecting to it.

[Warren Block]

Post by dweimer

Post by Shane Ambler

I would like to lock down the USB serial port adapter used on the UPS to
/dev/cuaU0, to make sure the UPS is always monitored and I will get a
clean shutdown in event of a power failure.
I believe that this requires setting a hint line of some sort in the
/boot/loader.conf file, but I am having trouble tracking down what this
should be, or maybe I am on the wrong track. Here is the current
information from the adpapters, the UPS adapter was connected at boot,
is on /dev/cuaU0, the other one was plugged in after boot, and is on
/dev/cuaU1.

start with man devd.conf
You can add your own devd files in /usr/local/etc/devd/
Something along the lines of -
attach 200 {
device-name "cuaU[0-9]+";
match "vendor" "0x067b";
match "product" "0x2303";
action "sleep 2; cd /dev; ln -s ${device-name} upsmonitor";
};
use usbconfig to get info. I am thinking with the similarity of the two
you may need to rely on bus and hubaddr or devaddr to keep each device
identified by usb port location.

OK, so I was looking in the wrong direction, which might explain why my
searching wasn't finding anything.
However I might still be out of luck, after doing some checking, and a reboot
the only difference I can find is below.
dev.uplcom.0.%location: bus=1 hubaddr=1 port=0 devaddr=2 interface=0
dev.uplcom.1.%location: bus=1 hubaddr=3 port=0 devaddr=3 interface=0

usbconfig may be able to get the device serial number, although they
may not be unique. Jamming useful scripts inside an action can be complicated.
It may be easier to just trigger an external script.

[dweimer]

Post by Warren Block

Post by dweimer

Post by Shane Ambler

I would like to lock down the USB serial port adapter used on the UPS to
/dev/cuaU0, to make sure the UPS is always monitored and I will get a
clean shutdown in event of a power failure.
I believe that this requires setting a hint line of some sort in the
/boot/loader.conf file, but I am having trouble tracking down what this
should be, or maybe I am on the wrong track. Here is the current
information from the adpapters, the UPS adapter was connected at boot,
is on /dev/cuaU0, the other one was plugged in after boot, and is on
/dev/cuaU1.

start with man devd.conf
You can add your own devd files in /usr/local/etc/devd/
Something along the lines of -
attach 200 {
device-name "cuaU[0-9]+";
match "vendor" "0x067b";
match "product" "0x2303";
action "sleep 2; cd /dev; ln -s ${device-name} upsmonitor";
};
use usbconfig to get info. I am thinking with the similarity of the two
you may need to rely on bus and hubaddr or devaddr to keep each device
identified by usb port location.

OK, so I was looking in the wrong direction, which might explain why
my searching wasn't finding anything.
However I might still be out of luck, after doing some checking, and
a reboot the only difference I can find is below.
dev.uplcom.0.%location: bus=1 hubaddr=1 port=0 devaddr=2 interface=0
dev.uplcom.1.%location: bus=1 hubaddr=3 port=0 devaddr=3 interface=0

usbconfig may be able to get the device serial number, although they
may not be unique. Jamming useful scripts inside an action can be
complicated. It may be easier to just trigger an external script.

That's just it, can't get usbconfig to give me anything different
between the two, they don't appear to have a serial number set on them.

# usbconfig -d ugen0.2 dump_device_desc
ugen0.2: <USB-Serial Controller Prolific Technology Inc.> at usbus0,
cfg=0 md=HOST spd=FULL (12Mbps) pwr=ON

bLength = 0x0012
bDescriptorType = 0x0001
bcdUSB = 0x0110
bDeviceClass = 0x0000
bDeviceSubClass = 0x0000
bDeviceProtocol = 0x0000
bMaxPacketSize0 = 0x0040
idVendor = 0x067b
idProduct = 0x2303
bcdDevice = 0x0300
iManufacturer = 0x0001 <Prolific Technology Inc.>
iProduct = 0x0002 <USB-Serial Controller>
iSerialNumber = 0x0000 <no string>
bNumConfigurations = 0x0001

# usbconfig -d ugen0.3 dump_device_desc
ugen0.3: <USB-Serial Controller Prolific Technology Inc.> at usbus0,
cfg=0 md=HOST spd=FULL (12Mbps) pwr=ON

bLength = 0x0012
bDescriptorType = 0x0001
bcdUSB = 0x0110
bDeviceClass = 0x0000
bDeviceSubClass = 0x0000
bDeviceProtocol = 0x0000
bMaxPacketSize0 = 0x0040
idVendor = 0x067b
idProduct = 0x2303
bcdDevice = 0x0300
iManufacturer = 0x0001 <Prolific Technology Inc.>
iProduct = 0x0002 <USB-Serial Controller>
iSerialNumber = 0x0000 <no string>
bNumConfigurations = 0x0001

[dweimer]

Post by dweimer

Post by Shane Ambler

I would like to lock down the USB serial port adapter used on the UPS to
/dev/cuaU0, to make sure the UPS is always monitored and I will get a
clean shutdown in event of a power failure.
I believe that this requires setting a hint line of some sort in the
/boot/loader.conf file, but I am having trouble tracking down what this
should be, or maybe I am on the wrong track. Here is the current
information from the adpapters, the UPS adapter was connected at boot,
is on /dev/cuaU0, the other one was plugged in after boot, and is on
/dev/cuaU1.

start with man devd.conf
You can add your own devd files in /usr/local/etc/devd/
Something along the lines of -
attach 200 {
device-name "cuaU[0-9]+";
match "vendor" "0x067b";
match "product" "0x2303";
action "sleep 2; cd /dev; ln -s ${device-name} upsmonitor";
};
use usbconfig to get info. I am thinking with the similarity of the two
you may need to rely on bus and hubaddr or devaddr to keep each device
identified by usb port location.

OK, so I was looking in the wrong direction, which might explain why
my searching wasn't finding anything.
However I might still be out of luck, after doing some checking, and
a reboot the only difference I can find is below.
dev.uplcom.0.%location: bus=1 hubaddr=1 port=0 devaddr=2 interface=0
dev.uplcom.1.%location: bus=1 hubaddr=3 port=0 devaddr=3 interface=0
The devices have switch at this point, all info from usbconfig,
dmesg, looks identical, these two lines from the sysctl -a | grep
"uplcom" output is all that changed, the hubaddr=1 and hubaddr=3 have
switched, however the man devd.conf has a variable list, to use, and
doesn't seem to have an option to match agains that hubaddr variable.
Variable Description
bus Device name of parent bus.
cdev Device node path if one is created by the devfs(5)
filesys-
tem.
cisproduct CIS-product.
cisvendor CIS-vendor.
class Device class.
device Device ID.
devclass Device Class (USB)
devsubclass Device Sub-class (USB)
device-name Name of attached/detached device.
endpoints Endpoint count (USB)
function Card functions.
interface Interface ID (USB)
intclass Interface Class (USB)
intprotocol Interface Protocol (USB)
intsubclass Interface Sub-class (USB)
manufacturer Manufacturer ID (pccard).
mode Peripheral mode (USB)
notify Match the value of the ``notify'' variable.
parent Parent device
port Hub port number (USB)
product Product ID (pccard/USB).
release Hardware revision (USB)
sernum Serial Number (USB).
slot Card slot.
subvendor Sub-vendor ID.
subdevice Sub-device ID.
subsystem Matches a subsystem of a system, see below.
system Matches a system type, see below.
type Type of notification, see below.
vendor Vendor ID.
But the action line above does give me an idea though, I should be
able to write a script to run at startup to find the line, and create
the link to the device. The only one I care about is the UPS
monitor,
as the other is only occasionally used, and I can easily check which
com port its on before connecting to it.

This probably wouldn't work for anyone else, but here is my solution in
case it does help someone else.

Created a new script in /usr/local/etc/rc.d/nutusblink
#!/bin/sh

# PROVIDE: NUTUSBLINK
# REQUIRE: NETWORKING
# BEFORE: nut
# KEYWORD: shutdown

. /etc/rc.subr

name="nutusblink"
start_cmd="nutusblink_start"
stop_cmd="nutusblink_stop"
rcvar="nutusblink_enable"


find_comport() {
grepstring='uplcom.*hubaddr='${nutusblink_hubaddr}
comnum=`sysctl -a | grep ${grepstring} | awk '{print $1}' | awk -F .
'{print $3}'`
}

nutusblink_start() {
find_comport
echo ""
echo "...Creating USB Serial Adapter Comport Link for NUT UPS
Monitoring..."
ln -s /dev/cuaU${comnum} /dev/${nutusblink_link}
echo " /dev/${nutusblink_link} Linked to /dev/cuaU${comnum}"
echo ""
}

nutusblink_stop() {
find_comport
echo ""
echo "...Removing USB Serial Adapter Comport Link for NUT UPS
Monitoring..."
rm /dev/${nutusblink_link}
echo " /dev/${nutusblink_link} No longer linked to
/dev/cuaU${comnum}"
echo ""
}

load_rc_config $name

: ${nutusblink_enable="NO"}
: ${nutusblink_hubaddr=""}
: ${nutusblink_link=""}

run_rc_command "$1"


Added these lines to /etc/rc.conf
# Create NUT USB Link
nutusblink_enable="YES"
nutusblink_hubaddr="3"
nutusblink_link="nutusblink"

End Result,
I now have a link /dev/nutusblink pointed at /dev/cuaU#, where # is the
correct port number. I have tested on a couple of reboots, and
configured NUT to use the link instead of the actual com port. Using
the BEFORE: nut in the script ensures that it gets ran before the NUT
process starts at boot.

Downside is that if I do unplug the USB serial port adapter, I have to
make sure you put it in the same port, and if its unplugged at boot, I
will need to run the script manually after plugging it in. I also
didn't bother with making sure it found a com port number before
creating the link, so if its not there, it will error, rather than
display a warning message, and not try to create a link.