Activate the serial console on my mini pc

[casabenedetti (Carlo)]

Continuing the discussion from Activate the serial console:

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I would like to activate the serial console on my machine.
Unfortunately, I am using a mini pc, so I cannot remove the video card and had to install a USB serial port.
I followed this procedure and tried with both straight and cross cable.
I could not get it to work. Where did I go wrong?
Here is my machine and the prolific USB card installed…

https://fireinfo.ipfire.org/profile/3402a2969f610247cadd6eea109917521f3d8410

Thank you in advance.

[cfusco]

@casabenedetti

Unfortunately, I am using a mini pc, so I cannot remove the video card and had to install a USB serial port.

This kind of hardware should need a device driver. Is the driver available in a standard Linux kernel? If yes, Is it compiled in IPFire kernel? Keep in mind that It is possible that the board has a serial port header. Many mini-ITX motherboards still harbor a 9 pins serial header.

I am not sure about these mini-pc though. Not a hardware expert. If the header exists, you would need to modify the case, but you could connect a cable from the header to a DB9 port and have a native serial port.

[casabenedetti (Carlo)]

I thank you for the diligent response.
I doubt if there are specific drivers for IPFire for my seiale prolific card I am using, although under linux, it should work.
My mini-pc is not modifiable. I can’t even expand the RAM. I don’t think it is set up for a “natural” serial port.
The alternative is to buy another IPFire-compatible USB serial port, but what do I buy?
From what you tell me, I think there is no other solution.

I know this pattern. However, I can try to open it. I hope the serial port I see is present.

[cfusco]

try to see the output of the dmesg command to see if you get something like this

I checked on my IPFire:

[root@ipfire cfusco]# modprobe pl2303
[root@ipfire cfusco]# lsmod | grep pl2303
pl2303                 28672  0
usbserial              65536  1 pl2303

the driver is available. It should work.

[casabenedetti (Carlo)]

I have the same results. I couldn’t get it to work anyway, though.

[cfusco]

What do you get with dmesg | grep tty?

[casabenedetti (Carlo)]

nothing…

[root@ipfire ~]# dmesg | grep tty
[root@ipfire ~]#

I went back to the “original graphics” condition, though. I did the reverse operation, canceling the serial. Does that have anything to do with it?

[cfusco]

Plug the hardware, issue modprobe pl2303 and then dmesg | grep tty, still nothing? Can you also check ls /dev/ttyUSB*?

EDIT: To clarify, all this in a working IPFire installation
EDIT2: also check lsusb and see if you have any message concerning USB to serial adapter

[casabenedetti (Carlo)]

Prolific hardware connected…

[root@ipfire ~]# modprobe pl2303
[root@ipfire ~]# dmesg | grep tty
[root@ipfire ~]#

Yes, Currently IPFire works and I can access the console either via HDMI cable or via Putty (IP Addressing).

file /dev/ttyUSB0 void

[cfusco]

@casabenedetti

file /dev/ttyUSB0 void

Is the file there? Don’t look at the size, just its presence. Next, please reboot with the hardware plugged in. Then post the output of lsmod and lsusb.

[casabenedetti (Carlo)]

Yes. The file is present. I’ll proceed with restarting IPFire and update you…

[casabenedetti (Carlo)]

[root@ipfire ~]# lsmod
Module                  Size  Used by
nfsv3                  57344  1
rpcsec_gss_krb5        32768  0
nfsv4                 995328  0
nfs                   483328  3 nfsv4,nfsv3
fscache               376832  1 nfs
netfs                  57344  1 fscache
snd_pcm_oss            69632  0
snd_mixer_oss          28672  1 snd_pcm_oss
nfsd                  651264  3
auth_rpcgss           155648  2 nfsd,rpcsec_gss_krb5
nfs_acl                16384  2 nfsd,nfsv3
lockd                 114688  3 nfsd,nfsv3,nfs
grace                  16384  2 nfsd,lockd
sunrpc                663552  22 nfsd,nfsv4,auth_rpcgss,lockd,nfsv3,rpcsec_gss_krb5,nfs_acl,nfs
tun                    61440  2
xt_REDIRECT            20480  1
xt_MASQUERADE          20480  1
xt_set                 20480  39
ip_set_hash_net        53248  18
xt_multiport           20480  20
ip_set                 61440  2 xt_set,ip_set_hash_net
xt_hashlimit           20480  2
xt_mac                 16384  157
xt_policy              16384  5
xt_TCPMSS              16384  1
xt_conntrack           16384  7
xt_comment             16384  14
ipt_REJECT             16384  5
nf_reject_ipv4         16384  1 ipt_REJECT
xt_LOG                 20480  94
xt_limit               16384  92
xt_mark                16384  48
xt_connmark            16384  2
nf_log_syslog          24576  94
iptable_raw            16384  0
iptable_mangle         16384  1
iptable_filter         16384  1
vfat                   24576  1
fat                    90112  1 vfat
snd_hda_codec_hdmi     81920  0
r8153_ecm              16384  0
snd_hda_codec_realtek   176128  1
cdc_ether              24576  1 r8153_ecm
snd_hda_codec_generic    98304  1 snd_hda_codec_realtek
ledtrig_audio          16384  1 snd_hda_codec_generic
i2c_algo_bit           16384  0
sch_cake               40960  4
fb_sys_fops            16384  0
syscopyarea            16384  0
sysfillrect            16384  0
sysimgblt              16384  0
intel_powerclamp       20480  0
snd_hda_intel          57344  0
coretemp               20480  0
snd_intel_dspcfg       20480  1 snd_hda_intel
kvm_intel             376832  0
snd_hda_codec         180224  4 snd_hda_codec_generic,snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec_realtek
pl2303                 28672  0
kvm                  1126400  1 kvm_intel
intel_xhci_usb_role_switch    16384  0
usbserial              65536  1 pl2303
roles                  20480  1 intel_xhci_usb_role_switch
snd_hda_core          122880  5 snd_hda_codec_generic,snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec,snd_hda_codec_realtek
iTCO_wdt               16384  0
iTCO_vendor_support    16384  1 iTCO_wdt
r8152                 131072  1 r8153_ecm
snd_hwdep              16384  1 snd_hda_codec
irqbypass              16384  1 kvm
snd_pcm               184320  5 snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec,snd_pcm_oss,snd_hda_core
processor_thermal_device_pci_legacy    16384  0
snd_timer              40960  1 snd_pcm
processor_thermal_device    20480  1 processor_thermal_device_pci_legacy
i2c_i801               36864  0
pcspkr                 16384  0
r8169                  94208  0
snd                   126976  10 snd_hda_codec_generic,snd_hda_codec_hdmi,snd_hwdep,snd_hda_intel,snd_hda_codec,snd_hda_codec_realtek,snd_timer,snd_pcm_oss,snd_pcm,snd_mixer_oss
processor_thermal_rfim    16384  1 processor_thermal_device
lpc_ich                28672  0
realtek                36864  1
i2c_smbus              20480  1 i2c_i801
soundcore              16384  1 snd
processor_thermal_mbox    16384  2 processor_thermal_rfim,processor_thermal_device
mfd_core               20480  1 lpc_ich
i2c_designware_platform    20480  0
intel_soc_dts_iosf     20480  1 processor_thermal_device_pci_legacy
i2c_designware_core    36864  1 i2c_designware_platform
i2c_core              114688  5 i2c_designware_platform,i2c_designware_core,i2c_algo_bit,i2c_smbus,i2c_i801
dw_dmac                16384  0
int3400_thermal        20480  0
int3403_thermal        20480  0
int3406_thermal        16384  0
acpi_thermal_rel       16384  1 int3400_thermal
int340x_thermal_zone    20480  2 int3403_thermal,processor_thermal_device
intel_int0002_vgpio    16384  1
ax88179_178a           36864  0
usbnet                 57344  3 r8153_ecm,cdc_ether,ax88179_178a
mii                    16384  3 usbnet,r8152,ax88179_178a
efivarfs               24576  1
crct10dif_pclmul       16384  1
crc32_pclmul           16384  0
polyval_generic        16384  0
ghash_clmulni_intel    16384  0
mmc_block              53248  5
video                  65536  1 int3406_thermal
sha512_ssse3           49152  0
sdhci_acpi             28672  0
wmi                    36864  1 video
sdhci                  81920  1 sdhci_acpi
mmc_core              208896  3 sdhci,mmc_block,sdhci_acpi
pinctrl_cherryview     49152  3
dm_mirror              28672  0
dm_region_hash         24576  1 dm_mirror
dm_log                 20480  2 dm_region_hash,dm_mirror
dm_mod                167936  2 dm_log,dm_mirror




[root@ipfire ~]# lsusb
Bus 002 Device 004: ID 0b95:1790 ASIX Electronics Corp. AX88179 Gigabit Ethernet
Bus 002 Device 002: ID 0bda:8153 Realtek Semiconductor Corp. RTL8153 Gigabit Ethernet Adapter
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 005: ID 8087:0a2a Intel Corp. Bluetooth wireless interface
Bus 001 Device 003: ID 0bda:8153 Realtek Semiconductor Corp. RTL8153 Gigabit Ethernet Adapter
Bus 001 Device 004: ID 067b:23a3 Prolific Technology, Inc. USB-Serial Controller
Bus 001 Device 002: ID 1a40:0101 Terminus Technology Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
[root@ipfire ~]#

The serial/hdmi “console switching,” is it automatic or do you have to configure IPFire with special commands?

As I see, it seems to me that IPFire sees the driver without any problems.

I suspect that IPFire, switches to the HDMI port excluding the serial console.

[cfusco]

@casabenedetti

As I see, it seems to me that IPFire sees the driver without any problems.

I agree.

@casabenedetti

The serial/hdmi “console switching,” is it automatic or do you have to configure IPFire with special commands?

there is a specific menu choice for the console install. Look for the instructions of the APU1 or 2 in the forum and you should see some screenshot. Otherwise you can follow the instructions from @arne_f in the original thread to activate it after the install. You need to change grub configuration file according to his suggestion (be careful to use /dev/ttyUSB0 as the device) and rebuild the boot loader. Message me if you need assistance. I do not have a lot of time but I can try to help.

[casabenedetti (Carlo)]

Yes, I had already tried that procedure.
Subsequently, I had replaced console=ttyS0 with console=ttyUSB0.
I found myself in an extreme condition: my IPFire would no longer start.
I preferred to reinstall the whole system. I had the backup ready and in about 15 minutes solved everything.
I just tried again in a virtual machine. This time, I replaced console=ttyS0 with console=/dev/ttyUSB0: SAME PROBLEM.
Here is what happens to IPFire at boot time, after applying that procedure (ttyUSB0)…

[cfusco]

try ttyUSB0 without /dev

[casabenedetti (Carlo)]

console=ttyUSB0
already tried at the start. Same problem.

[cfusco]

did you rebuild the boot loader after changing the configuration of grub?

grub-mkconfig -o /boot/grub/grub.cfg

[casabenedetti (Carlo)]

Yes, from terminal I launched…
/usr/sbin/grub-mkconfig -o /boot/grub/grub.cfg

With console=ttyS0 no problem at startup. But neither serial nor hdmi works. In my case.

[cfusco]

Your terminal connected to the minipc is a laptop running PuTTY? If yes, do you have a correct configuration? In particular:

1. Specify the serial line to which your device is connected (e.g., COM1, COM2, etc.).
2. Set the baud rate to 115200, which is the speed specified in the GRUB_SERIAL_COMMAND line.
3. Make sure the Data bits are set to 8, as indicated by 115200n8 in the console=ttyS0,115200n8 line.
4. Set the Stop bits to 1, as the 115200n8 notation implies.
5. Set the Parity to None, as there is no parity specified in the console=ttyS0,115200n8 line.

EDIT, this should boot though, regardless whether the connection is correct.

[casabenedetti (Carlo)]

Yes, I think I have carried out what I said correctly.

@cfusco

EDIT, this should boot though, regardless whether the connection is correct.

Indeed, I do not explain the extreme condition. Yet I think I performed the steps to the letter.