Detect Serial card on linux

Six Serial port is not detect on linux and my linux kernel version is 2.6.
How to detect Six serial port on linux


To detect any serial ports in Linux, simply use dmesg command as shown below.

# dmesg | grep sda			[Detect Hard Disk]
# dmesg | grep -i usb		        [Detect USB Device]
# dmesg | grep -i tty		        [Detect TTy]
# dmesg | grep -i memory	        [Detect Memory]

For more information and usage about dmesg can be found at:

Not really very clear above.

Serial ports have a device name of tty so to find out if Linux has recognized your ports you would type:
dmesg | grep tty

If you get nothing back from the code in the terminal, Linux did not recognize your ports / card. If it did not, let me know your version of Ubuntu, exact kernel version, and what card it is (usb, pci, isa, maker and model… )

If you DID get anything back, it is indeed recognizing your card, and your problem is a configuration one.

But @poetfreak, what I’ve mentioned that also correct, may I know where it’s not clear to understand? Can you please explain me…:slight_smile:

You mentioned detecting all kinds of hardware with dmesg, which could lead to confusion as to which one of those commands was used for his specific question is all. :wink: Plus most new to linux do not know that tty is serial. :smiley:

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I have six serial port. Two serial port is on board and remaining 4 port i am connecting pci card.
Four port is detect on my system but 2 port is not detect on kernel version 2.6.
But i loaded latest kernel version and pass the kernel parameter (8250.nr_uarts=6) and run command dmesg | grep tty then i will show detect 6 serial port.

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It’s great that you finally solved yourself, but let me know did updating your old Kernel to latest version fixed your problem?

i’m installing kernel 4.0 and resolved my issue.
But tell me one thing, is it possible more than 4 serial port connect on old version.


Good, but no idea about old version of Kernel and how it detects serial ports…

No problem sir, Still my issue is resolved
And Thank you helping me :blush:

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