I'm using 6.1.9 with a Windows VM passing through a Prolific USB dual serial port.

 

I have modified the XML to pass through the 2 devices manually as the GUI does not support multiple devices with the same name.

 

Here is the XML.

 

    <hostdev mode='subsystem' type='usb' managed='yes'>
      <source>
        <address bus='1' device='22'/>
      </source>
      <alias name='hostdev3'/>
    </hostdev>
    <hostdev mode='subsystem' type='usb' managed='yes'>
      <source>
        <address bus='1' device='21'/>
      </source>
      <alias name='hostdev4'/>
    </hostdev>

 

Here are my USB devices

 

Bus 008 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 007 Device 003: ID 0403:e0e8 Future Technology Devices International, Ltd 
Bus 007 Device 002: ID 1a40:0101 Terminus Technology Inc. Hub
Bus 007 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 006 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 005 Device 003: ID 0951:160e Kingston Technology 
Bus 005 Device 002: ID 0658:0200 Sigma Designs, Inc. 
Bus 005 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 019: ID 0a5c:200a Broadcom Corp. BCM2035 Bluetooth dongle
Bus 001 Device 018: ID 03eb:204b Atmel Corp. LUFA USB to Serial Adapter Project
Bus 001 Device 017: ID 050d:0304 Belkin Components FSU304 USB 2.0 - 4 Ports Hub
Bus 001 Device 003: ID 1a40:0101 Terminus Technology Inc. Hub
Bus 001 Device 025: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
Bus 001 Device 024: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
Bus 001 Device 023: ID 05e3:0608 Genesys Logic, Inc. Hub
Bus 001 Device 011: ID 0557:2419 ATEN International Co., Ltd 
Bus 001 Device 008: ID 0557:7000 ATEN International Co., Ltd Hub
Bus 001 Device 005: ID 0403:6001 Future Technology Devices International, Ltd FT232 USB-Serial (UART) IC
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

 

The IDs for the Prolific serial ports have changed to 25 and 24 for the serial ports. Yesterday they were 22 and 21 as per the XML.

 

Is there a way of stopping the constant change so that I don't have to keep adjusting the XML?

 

Motherboard is a SuperMicro x10sra-f

 

Anyone any ideas?

 

thanks

Anyone any ideas?

 

Slippery little buggers!

 

No direct experience here, but this happens with other devices too, and you have to find a more permanent way to access them.  For example, drive symbols change often, so you have to use by_id to grab them in a way they won't slip out of.

Thanks. Is 6.2 any better in this regard?

I haven't done anything with VM's yet, so not the best answerer.  But I believe the latest 6.2 RC's have small changes in USB handling, possibly kernel related.  Can't say if that will help or hurt you.  But I don't recall others having your issue.