I have someone wanting to connect to the serial management port of a switch from a PC running CentOS6. The management port on the switch is apparently baud 9600, 8 data bits, 1 stop bit & no parity They have plugged in a cable to connect and the output from lsusb is:-
Bus 001 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 002: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
Bus 001 Device 003: ID 04b3:3025 IBM Corp. NetVista Full Width Keyboard
Bus 001 Device 004: ID 03f0:094a Hewlett-Packard Optical Mouse [672662-001]
lsusb -vs 1:2
shows the device in question and gives me:-
# lsusb -vs 1:2
Bus 001 Device 002: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 1.10
bDeviceClass 0 (Defined at Interface level)
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x067b Prolific Technology, Inc.
idProduct 0x2303 PL2303 Serial Port
bcdDevice 3.00
iManufacturer 1 Prolific Technology Inc.
iProduct 2 USB-Serial Controller D
iSerial 3 00000C7B
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 39
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xa0
(Bus Powered)
Remote Wakeup
MaxPower 100mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 3
bInterfaceClass 255 Vendor Specific Class
bInterfaceSubClass 0
bInterfaceProtocol 0
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x000a 1x 10 bytes
bInterval 1
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x02 EP 2 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0040 1x 64 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x83 EP 3 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0040 1x 64 bytes
bInterval 0
Device Status: 0x0000
(Bus Powered)
The devices I find with usb in the name are these:-
/dev/serial/by-id/usb-Prolific_Technology_Inc._USB-Serial_Controller_D_00000C7B-if00-port0
/dev/serial/by-path/pci-0000:00:14.0-usb-0:3:1.0-port0
/dev/ttyUSB0
/dev/usbmon2
/dev/bus/usb
/dev/usbmon1
/dev/.udev/links/input\x2fby-path\x2fpci-0000:00:14.0-usb-0:5:1.0-event-mouse
/dev/.udev/links/input\x2fby-id\x2fusb-PixArt_HP_USB_Optical_Mouse-event-mouse
/dev/.udev/links/input\x2fby-path\x2fpci-0000:00:14.0-usb-0:4:1.0-event-kbd
/dev/.udev/links/input\x2fby-id\x2fusb-LITE-ON_Technology_USB_NetVista_Full_Width_Keyboard.-event-kbd
/dev/.udev/links/serial\x2fby-id\x2fusb-Prolific_Technology_Inc._USB-Serial_Controller_D_00000C7B-if00-port0
/dev/.udev/links/serial\x2fby-path\x2fpci-0000:00:14.0-usb-0:3:1.0-port0
/dev/.udev/links/input\x2fby-path\x2fpci-0000:00:14.0-usb-0:5:1.0-mouse
/dev/.udev/links/input\x2fby-id\x2fusb-PixArt_HP_USB_Optical_Mouse-mouse
/dev/.udev/db/tty:ttyUSB0
/dev/.udev/db/usbmon:usbmon0
/dev/.udev/db/usb:1-5
/dev/.udev/db/usb:1-4
/dev/.udev/db/usb:1-3
/dev/.udev/db/usb:usb2
/dev/.udev/db/usb:usb1
/dev/.udev/db/usbmon:usbmon2
/dev/.udev/db/usbmon:usbmon1
/dev/input/by-path/pci-0000:00:14.0-usb-0:5:1.0-event-mouse
/dev/input/by-path/pci-0000:00:14.0-usb-0:4:1.0-event-kbd
/dev/input/by-path/pci-0000:00:14.0-usb-0:5:1.0-mouse
/dev/input/by-id/usb-PixArt_HP_USB_Optical_Mouse-event-mouse
/dev/input/by-id/usb-LITE-ON_Technology_USB_NetVista_Full_Width_Keyboard.-event-kbd
/dev/input/by-id/usb-PixArt_HP_USB_Optical_Mouse-mouse
/dev/usbmon0
Assuming that I have to create a symbolic link as /dev/modem, what do I point it at? I've tried a few such as /dev/ttyUSB0, /dev/bus/usb/001/002 and the like, but I'm not sure how to test I've got anything right.
It's been suggested that the tool to use is minicom and I've set up the connect speed and negotiation as I've been told the serial port on the switch will expect but no output (not even rubbish) on screen. It's wanting a devices called /dev/modem which is why I presume i just need to create the link.
It's all a bit odd because it is a remote site, but the network team need to get on the serial management port of one of the other switches. They are hoping we can save a journey.
Am I even using the right approach with the right tools? For all I know, minicom might be offering dial-in to my server rather than driving a serial line the other way.
Kind regards,
Robin