ProLiant Servers (ML,DL,SL)
Showing results for 
Search instead for 
Did you mean: 

ML310 COM port stuck at 115200 in Linux (CentOS 6.6)

Occasional Visitor

ML310 COM port stuck at 115200 in Linux (CentOS 6.6)



We've a customer with an ML310 Proliant server running CentOS 6.6 (x86-64) that is trying to access our legacy serial device (which requires a 9600 baud connection) running on /dev/ttyS0. The device works fine on the old server they used to use but on the new one it simply won't work.


At first I assumed it was the iLO settings but I've checked and double-checked and the iLO serial is definitely disabled in both iLO and RBSU.


On top of that, a modem connected to the same port will work fine.


However it seems (we can see this by running ATI4 on the USR modem, which reports DTE speed) that no matter to what I set the serial port speed, the actual speed of the port stays at 115200.


Is this a known problem? Is there a way to stop the server forcing the speed in this way?


I don't have physical access to the server but I can run the various hp configuration tools...


conrep gives:


<Section name="BIOS_Console" helptext="Used to select the port for the BIOS console">Disabled</Section>
<Section name="BIOS_Baud_Rate" helptext="BIOS console communications settings">9600</Section>

<Section name="BIOS_Type" helptext="Terminal Emulation Mode of BIOS Serial Console">VT100</Section>
<Section name="EMS_Console" helptext="Used to select the port for the EMS console">Disabled</Section>


hponcfg -a gives:




(as far as I can tell from the docs, status 1 means "iLO Serial Disabled", speed 1 means 9600 baud)


Finally hpasmcli gives:


hpasmcli> show serial embedded
Embedded serial port A: COM1
Embedded serial port B: COM2
hpasmcli> show serial bios
BIOS console redirection port is currently disabled.


stty, setserial and minicom all show the serial port speed change to 9600 successfully (which implies that there's nothing at the software level changing the speed in the background), but (as I said) the modem still reports that the actual port speed is 115200.


Any suggestions appreciated.