4 Replies Latest reply on Jul 31, 2011 10:10 PM by smsf

    Adding serial port PCI card to existing ESX host

    smsf Novice

      My DL385G2 comes with 1 serial port (COM1). In BIOS, COM2 was set to virual serial port (which I don't use so I disabled it).


      I installed a 2-port PCI-E serial card (Startech PEX2S550) and ran Kudzu on the host console. Kudzu detected the card and configured it. I restarted the host to make sure the ports are detected and initialized properly.




      After the reboot, I noticed some ttyS: 1 input overrun(s) messages on the console. I don't know if this has anything to do with the new ports but I did not notice them before I restarted the system.




      Anyway, even though I should have three available serial ports (ttyS0, ttyS1, and ttyS2), ESX only allows me to add ttyS0 and ttyS1 to my VMs. I added ttyS1 to one of my VMs but it doesn't work (tested with an external modem).




      Am I doing the right things in trying to expand the number of COM ports on my ESX host? Is there a recommended way to add additional serial ports to ESX? How can I test the COM ports under ESX host (Linux command to probe the port)?




      System config:




      ESX 3.0.1 with patches up until Dec '07.

      HP DL385 G2 (1 built-in COM port)

      Virtual serial port is disabled in ESX host's BIOS.



      Looking at the  /var/log/messages, I see the following:



      Mar 19 08:51:46 vmhost01 kernel: pty: 256 Unix98 ptys configured

      Mar 19 08:51:46 vmhost01 kernel: Serial driver version 5.05c (2001-07-08) with MANY_PORTS MULTIPORT SHARE_IRQ SERIAL_PCI enabled

      Mar 19 08:51:46 vmhost01 kernel: ttyS0 at 0x03f8 (irq = 4) is a 16550A



      I guess this means it's not detecting the additional ports.

        • 1. Re: Adding serial port PCI card to existing ESX host
          jlanders Expert
          VMware Employees





          I believe the Startech PEX2S550 uses the NetMos 9835 controller. You should check by typing 'lspc -v' at the command prompt in the Service Console. The Moschip website has a document describing how to configure the card, if nothing was provided by Startech. The serial ports may be set to ttyS3 and ttyS4, although you should see a message indicating that in dmesg at boot time. If nothing else works, try disabling both on-board serial ports and check if you can get the Service Console kernel to recognize the card. If that doesn't work, you may want to check that the card is functioning by testing it in a non-ESX system.









          1 person found this helpful
          • 2. Re: Adding serial port PCI card to existing ESX host
            smsf Novice



            Thanks for your response.



            You're right, the chipset is MosChip MCS9835CV. According to the Moschip website (http://www.moschip.com/html/MCS9901.html), the 9901 product (which looks like is uses this chip) is support under Linux kernel 2.6 and higher, which rules out ESX 3.0.1 (kernel 2.4).


            However, I found this:



            There is no Linux driver/source code for MCS98XX. You have to manually

            configure the ports on Linux. Please use the following steps:



            • setserial /dev/ttyS2 port 0xecf8 UART 16550A irq 10 Baud_base 115200

            • setserial /dev/ttyS3 port 0xece8 UART 16550A irq 10 Baud_base 115200

            • /sbin/modprobe parport_pc io=0x3f8,0xecd8 irq=4,10


            Note: Use the appropriate IRQ number as per your system.


            Here's a snippet of lspci -v result:



            09:00.0 Serial controller: NetMos Technology 222N-2 I/O Card (2S1P) (rev 01) (prog-if 02 )+

            Subsystem: LSI Logic / Symbios Logic: Unknown device 0002

            Flags: medium devsel, IRQ 22

            I/O ports at 4000

            I/O ports at 4008

            I/O ports at 4010

            I/O ports at 4018

            I/O ports at 4020

            I/O ports at 4030



            I'll try it and report back. Hopefully this works.

            • 3. Re: Adding serial port PCI card to existing ESX host
              ericksonrs Lurker

              Did you ever get this to work?  I am trying with a simial card from startech, running esxi 4.1.  Thanks for your help!

              • 4. Re: Adding serial port PCI card to existing ESX host
                smsf Novice

                Wow, I totally forgot about this thread.


                The result of my experiment? It didn't work. I decided to forgo virtualizing the com port.