pikvm/pages/Community_FAQ.md

Community FAQ

Can I power the Pi via POE?

• Yes! But you will still need to ensure you isolate the 5v connection between the Raspberry Pi and host PC to prevent backpower issues that can cause instability or damage to either the host PC or the Pi.

Do I need a power splitter? Why do I need one?

• Yes for RPi4, No for Zerow
• Yes, otherwise you could back power the pi and or the target
• You can get a Y cable from amazon and mod one of the leads - Please see getting started guide
• You can get a power splitter board from Tindi or PiShop (Links provided below)
• If you have the v3 HAT - This is built in

I can't get the KVM KB to work on my ZeroW!

Make sure that you did NOT modify your config.txt file, this is the default:

# See /boot/overlays/README for all available options
initramfs initramfs-linux.img followkernel
hdmi_force_hotplug=1
gpu_mem=64
enable_uart=1
dtoverlay=tc358743,i2c_pins_28_29=1
dtoverlay=disable-bt
dtoverlay=dwc2,dr_mode=peripheral

Can I use a KB on my ZeroW?

• Yes but kb/mouse passthrough will not work. Its one or the other
  • Host mode - Comment out dtoverlay=dwc2
  • Passthrough mode - Uncomment out dtoverlay=dwc2

Can you have the pi-kvm(RPi4) connected along with a monitor?

• If you have two outputs, you may be able to use screen mirroring from the OS but not BIOS
• If you have one output or need access from both a local monitor or Pi-KVM at boot time, one of the following options may work:
  • Passthrough HDMI capture devices (sometimes referred to as a loop capture device). The Elgato devices DO NOT WORK! Look for Linux OS support when choosing a device, the expected price range is about $35-$70 US.
  • Depending on your capture device, an HDMI splitter may work but will need what is called an EDID (Extended Device ID) generator, the monitor and capture device both generate EDID so the splitter must produce its own separate EDID for the host.
  • Look for HDMI splitters - although there have been reports that these are not stable
    • Please use the search function in Discord, some users have had sucess in getting this to work but your mileage may vary
  • The better solution is to capture the stream in a dir and then use VLC to stream to that capture on another computer. This will result in fps loss.

Wouldn't it be good to have different hostnames for your multitude of pi-kvms?

Yes! And it's easy to do! Using a SSH session or the web terminal:

• Make sure you're root, if you're not root use the su command to become root
• Enter read write mode of the PiKVM by executing the rw command
• Execute: hostnamectl set-hostname yournewhostname.domain
• Optional: Edit /etc/kvmd/meta.yaml to alter the displayed hostname in the web UI
• Reboot the pikvm

I can't make edits?!?!?

• Did you issue a rw before updating/editing?

In the Web Terminal, how do I get root?

• Type su -
• Put root for the password

Why are you using Arch Linux?

• The developer was more familiar with Arch Linux so this was chosen as the base operating system. As a Linux distribution, it has more in common than not with other distributions.
  
  As an appliance, users are not expected to interact with the host operating system often, if at all. There are some distribution-specific differences, by default networking is done using either systemd-networkd or netctl but NetworkManager can be used as a replacement if one prefers.

Is Pi-KVM an OS?

• No, this is merely riding on top of an existing OS

I want to do something not related to Pi-KVM

• It's recommended that you review Arch documents related to what you want to do, while there are several folks in discord who can help, there is no obligation...they do it for the feels. So if you don't get an answer within the time frame you are looking for, it's advised you start google searching for what you want.

Can this be used in any other distro’s like Rasbian?

• Not at this time, maybe in the future

My Pi keeps disconnecting from my wireless! What do I do?

• Edit "/etc/conf.d/wireless-regdom" and look for your region and uncomment it. Example: WIRELESS_REGDOM="US"

I want a static IP!!

• You can configure systemd-networkd for a static address for ethernet NIC. Config file is /etc/systemd/network/eth0.network
• For wireless adapter, config file is /etc/netctl/wlan0-
• See pikvm/wifi_config.md at master · pikvm/pikvm · GitHub for details on how to get basic wireless config with DHCP going. Afterwards, you’ll need to edit the /etc/netctl/wlan0- file changing the IP=dhcp line with the following lines updated to reflect your network:

IP=static
Address=('192.168.X.XXX/24')
Gateway=('192.168.X.X')
DNS=("192.168.X.X 1.0.0.1 1.1.1.1")

• You can also reserve the IP in your dhcp server (Quicker)

Why do I keep getting a different IP?

• Add to, /etc/systemd/network/eth0.network

[DHCP]
ClientIdentifier=mac

• Reserve the DHCP ip in your server/router
• The most likely reason is piKVM root FS is RO, so it cannot cache its lease and ask for the same one next time
• DHCP servers look at a variety of things to determine if the same host is asking for the same IP, some look at MAC addresses, some look at the session string
• [ADVANCED] If you want to replace systemd-networkd with NetworkManager
  • rw; pacman -Sy networkmanager and use nmcli or nmtui to configure your interface. Then systemctl disable --now systemd-networkd and systemctl disable --now systemd-resolved systemctl enable --now NetworkManager ln -sf /run/NetworkManager/resolv.conf /etc/resolv.conf and should be good, reboot to make sure services stay on or off (as desired) or put system back in RO mode with ro

HELP!! I can't find the IP on the ZeroW/RPi4

• Open a browser and type: pikvm, still doesnt work?
• Use the FING mobile app to scan your network, its free
• Install Angry IP scanner, tools/preferences/Display results in the results list/Select Alive hosts, modify IP range, hit start
• Using FF, navigate to https://pikvm
  • Open web terminal and go to root, rw then nano /etc/issue
  • add ‘IP: \4’
  • Once you reboot, you will now see the IP in the upper right

arp -a | grep below is a list of MAC's for Raspberry Pi
	B8:27:EB:xx:xx:xx	B8-27-EB-xx-xx-xx	B827.EBxx.xxxx
	DC:A6:32:xx:xx:xx	DC-A6-32-xx-xx-xx	DCA6.32xx.xxxx
	E4:5F:01:xx:xx:xx	E4-5F-01-xx-xx-xx	E45F.01xx.xxxx
Power shell: arp -a | findstr 'b8-27-eb' (Replace with the above, all lower case)

Help! I ran out of room! What now?

• You’ve cached package updates you no longer need.
• Enter read/write mode by executing rw as root
• Execute the following as root to clear the package cache

rm -rf /var/cache/pacman/pkg/*

• Exit read/write mode by executing ro as root
• You can also use gparted to resize partitions without losing data, although

Can you connect a camera to this and still make pikvm functional?

• Yes, any cheapo webcam can be used in place of the usb dongle, please use the usb image

I have a question that is not answered here!! Now what?

• Please look at all pins on Discord
• Please look in #news on Discord

I want the v3 hat!! Where do I get it??

• At this time it is not available, due to the current pandemic the factories are running at a much slower rate

HELP!! Something isn't working!!

• What was the last thing or most recent thing you did? Did you undo it?
• Did you hook this to anything else? If not why not?
• Did you try different cables?

Things to do after initial install:

• Fix date: 'timedatectl list-timezones' then 'timedatectl set-timezone America/Los_Angeles' (Change to your location)
• Update Pi-KVM, follow #news on Discord for instructions
• Enable Avahi-Daemon (A Zeroconf daemon) to allow finding the pikvm via mDNS queries as pikvm.local
  • pacman -S avahi nss-mdns gtk3 python-dbus python-gobject
  • Enable the Avahi daemon in order to make it persistent after reboot:

systemctl enable avahi-daemon.service

• Start the DBus (if not already running) & Avahi daemons:

systemctl start dbus.service
systemctl start avahi-daemon.service

• Setup a NFS share to give read/write storage on the read only pikvm
  • Note this does assume you already have a NFS server on your network and accessible to pikvm
  • Source https://linuxhint.com/install_configure_nfs/

pacman -S nfs-utils
showmount -e 192.168.1.XXX
mount -t nfs 192.168.1.XXX:/volume1/Data /mnt/Data
nano /etc/fstab

Add To the bottom of the file

192.168.1.XXX:/volume1/Data /mnt/Data nfs      auto,rw,soft    0 0

Can you use an iPad on PiKVM?

• Yes, with the correct hardware you can control an iPad
• Yes, activate VNC and use JUMP app(Full featured but more expensive), or bVNC(Not recommended, lack luster features but cheap). RealVNC does NOT work

Can I use RealVNC to connect to PiKVM?

• No, RealVNC is not a real vnc so will not work

Troubleshooting

• It is expected that you are aware of basic networking while working on this project and that you have read up on the project prior to going to Discord

  • Do you know the IP?

  • Can you ping the IP?

  • Did you swap cables?

  • Did you swap the eth port to a known working eth port?

  • Do you have access to another router or switch?

  • Did you change ports on the router/switch?

  • RPi4 - Did you hook up a monitor? Once logged in, can you ping to your gateway? Other IP's on the same network?

  • Did you connect a monitor to the target? Does it work?

  • Did you connect the PIKVM to the target directly? Does it work?

Common Commands for troubleshooting Pi-KVM

• journalctl -u kvmd
• journalctl -u kvmd-vnc
• journalctl -u kvmd-ipmi

Common ARCH commands

• search - pacman -Ss 'the thing'
• install - pacman -S 'the thing'

Common wifi commands

• iwconfig manipulate the basic wireless parameters
• iwlist allow to initiate scanning and list frequencies, bit-rates, encryption keys…
• iwspy allow to get per node link quality
• iwpriv allow to manipulate the Wireless Extensions specific to a driver (private)
• Some examples

iw dev wlan0 scan | egrep "signal:|SSID:" | sed -e "s/\tsignal: //" -e "s/\tSSID: //" | awk '{ORS = (NR % 2 == 0)? "\n" : " "; print}' | sort

iwlist wlan0 scan | egrep "Cell|ESSID|Signal|Rates"

iwlist wlan0 scan

iw wlan0 info

Bootup/power issues

• PiKVM won’t boot past “rainbow” screen
  • Are you plugged into the right HDMI port? Needs to be the one next to the power
  • Have you reflashed your SD card?

PiKVM Complains about low power warnings

• Are you using a proper power supply? Not one you hacked together
• Some USB power bricks advertise 5V @ 2.1A or higher, but can’t deliver consistent 5V. Best to use rpi foundation recommended power supplies

USB Video Capture Issues

• TBD

HDMI-CSI Capture issues

• Are you sure it's a bridge and not an extender? There is a difference
• Did you make sure it's plugged into the right port? It needs to say Camera NOT Display
• Did you try another ribbon cable?
• Did you reseat the ribbon cable?
• Is the ribbon cable facing the right way? Needs to be towards the PCB (Green or Black)

Capturing video from non HDMI sources

• TBD

Keyboard/Mouse Issues

• TBD

OTG Keyboard/Mouse Connection

• TBD

Arduino Keyboard Mouse Connection (UART wiring)

• TBD

Arduino Keyboard/Mouse Connection (SPI Wiring)

• TBD

ATX Control Issues

• TBD

HDMI KVM Interface Issues

• TBD

Connection issues

Misc stuff

• Fully working example of a Pi4 USB-HDMI KVM attached to AIMOS 4-port HDMI KVM switch, with keyboard hotkey switching between inputs, and mass storage media emulation on a Pi Zero W https://docs.google.com/document/d/1wgBZHxwpbJWkJBD3I8ZkZxSDxt0DdNDDYRNtVoL_vK4

Useful links

• Pi-KVM Power/Data OTG splitter boards
  • https://www.pishop.us/product/usb-pwr-splitter/
  • https://www.pishop.us/product/usb-c-pwr-splitter/
  • https://www.tomshardware.com/how-to/kvm-over-ip-raspberry-pi - Very good article on PI-KVM setup

As of March 2021, Out of Stock or hard to get, all have exceptionally LONG shipping dates - Could try AliExpress or get a usb2hdmi dongle from Amazon, please ask or search in Discord for the best known working one

Ezcoo KVM
CSI2-HDMI bridge w/ TC358743XBG chip
Alternative names for the same devices:
Tiamu	  	Sling	    	Yazan	    	Ningwang	Essenc	  	Geekworm
Fauge	  	Haudang	  	AKAT	    	Docoop	    	Katigan	  	Lyusa (recommended by mdevaev)
LNIMI	  	cherrypop	Lopbinte	Uang	      	Tuneway	  	Mustwell
Facibom		Binchil	  	Cobeky	  	Ctzrzyt	    	Davitu