Peter Kieser – Passionately pursuing excellence.

deCONZ VNC access without full blown Xorg install

November 23, 2020November 23, 2020 Peter Leave a comment

deCONZ / Phoscon-GW recommends a full blown Xorg install on a Raspberry Pi to access their GUI. deCONZ is a utility to work with Zigbee controller provided by Raspbee / Conbee. deCONZ GUI provides more advanced control of Zigbee devices, and has functionality that is not available via web interface/REST API.

No need to install a full blown UI if you want to run headless. These instructions are for Raspbian.

Make sure to disable and stop existing deconz services if enabled:

systemctl disable deconz
systemctl stop deconz

You may also have deconz-gui service if you have followed their install guide, so make sure to disable and stop this as well if applicable.

Install TigerVNC which we will use to provide headless VNC access to the GUI:

apt-get install tigervnc-standalone-server

You will create a new systemd service definition, which is outlined below .

/etc/systemd/system/deconz-vnc.service

[Unit]
Description=deCONZ: ZigBee gateway -- GUI/REST API VNC
Wants=deconz-init.service deconz-update.service

[Service]
User=1000
Environment="DISPLAY=:0"
ExecStartPre=/usr/bin/tigervncserver -geometry 1024x768 -useold -SecurityTypes None -localhost yes -noxstartup "$DISPLAY"
ExecStart=/usr/bin/deCONZ --http-port=80
Restart=on-failure
StartLimitIntervalSec=0
RestartSec=30
AmbientCapabilities=CAP_NET_BIND_SERVICE CAP_KILL CAP_SYS_BOOT CAP_SYS_TIME

[Install]
WantedBy=multi-user.target

Then reload systemd, enable and start the newly created service:

systemctl daemon-reload
systemctl enable deconz-vnc
systemctl start deconz-vnc

Once this is done you can setup a SSH port forward to localhost:5900 and access deCONZ GUI using your favourite VNC viewer.

Home Assistant sensors and CyberPower UPS via RMCARD205

November 16, 2020November 16, 2020 Peter

RMCARD205 supplies metrics via SNMP for all supported CyberPower UPS. Who doesn't want to display power usage on their UPS via Home Assistant?

I created a "package" for CyberPower UPS RMCARD that exports data via SNMP. This assumes your default read-only community is named public.

packages/ups.yaml:

sensor:
  - platform: snmp
    scan_interval: 60
    name: ups_nompower
    host: x.x.x.x
    baseoid: 1.3.6.1.4.1.3808.1.1.1.4.2.5.0
    accept_errors: true
    unit_of_measurement: Watts
  - platform: snmp
    scan_interval: 60
    name: ups_nominv
    host: x.x.x.x
    baseoid: 1.3.6.1.4.1.3808.1.1.1.3.2.1.0
    accept_errors: true
    unit_of_measurement: Volts
    value_template: '{{((value | int) / 10) | int}}'
  - platform: snmp
    scan_interval: 60
    name: ups_itemp
    host: x.x.x.x
    baseoid: 1.3.6.1.4.1.3808.1.1.1.2.2.3.0
    accept_errors: true
    unit_of_measurement: "°C"
  - platform: snmp
    scan_interval: 60
    name: ups_timeleft
    host: x.x.x.x
    baseoid: 1.3.6.1.4.1.3808.1.1.1.2.2.4.0
    accept_errors: true
    unit_of_measurement: 'minutes'
    value_template: '{{((value | int) / 6000) | int}}'
  - platform: snmp
    scan_interval: 30
    name: ups_status
    host: x.x.x.x
    baseoid: 1.3.6.1.4.1.3808.1.1.1.4.1.1.0
    accept_errors: true
    value_template: >-
      {% set status = (value | int) %}
      {%- if status == 2 -%}
      Online
      {%- elif status ==  3 -%}
      On Battery
      {%- elif status ==  4 -%}
      On Boost
      {%- elif status ==  5 -%}
      On Sleep
      {%- elif status ==  6 -%}
      Off
      {%- elif status ==  7 -%}
      Rebooting
      {%- elif status ==  8 -%}
      On ECO
      {%- elif status ==  9 -%}
      On Bypass
      {%- elif status ==  10 -%}
      On Buck
      {%- elif status ==  11 -%}
      On Overload
      {%- else -%}
      Unknown
      {%- endif -%}
      
group:
  ups:
    name: UPS
    entities:
      - sensor.ups_status
      - sensor.ups_nompower
      - sensor.ups_nominv
      - sensor.ups_itemp
      - sensor.ups_timeleft

homeassistant:
  customize:
    sensor.ups_nompower:
      friendly_name: 'UPS Nominal Output Power'
      icon: mdi:flash
    sensor.ups_nominv:
      friendly_name: 'UPS Nominal Input Voltage'
      icon: mdi:flash
    sensor.ups_status:
      friendly_name: 'UPS Status'
      icon: mdi:information-outline
    sensor.ups_itemp:
      friendly_name: 'UPS Internal Temperature'
      icon: mdi:thermometer
    sensor.ups_timeleft:
      friendly_name: 'UPS Time Left'
      icon: mdi:clock-alert

Supermicro IPMI Virtual Media and Samba 4.11 (Ubuntu 20.04)

May 14, 2020May 14, 2020 Peter

Unable to mount an ISO using Virtual Media function available on Supermicro IPMI with Samba 4.11 (used in Ubuntu 20.04)?

You successfully set the Share Host, and Path to Image. You select "Mount", and Device 1 virtual media status does not change to "There is an iso file mounted." It stays at "No disk emulation set."

Samba 4.11 in Ubuntu 20.04 has changed the server minimum protocol supported. To enable IPMI to work with the new Samba, in /etc/samba/smb.conf you need to change/add server min protocol to NT1.

[global]
server min protocol = NT1

Then you can reload Samba:

smbcontrol all reload-config

NetGear GS108T, NetGear R7000 Nighthawk AP and Intel igb/e1000e on Linux: adapter reset

June 29, 2019June 29, 2019 Peter

What's the issue?

At home I have a NetGear GS108T with a NetGear R7000 serving as an Access Point. My Ubuntu 16.04 machine which functions as a hypervisor (qemu/kvm and openvswitch) has an "adapter reset"/"transmit queue timed out" error on igb and e1000e Intel NICs and causes a 30-60 second outage when my NetGear R7000 Access Point restarts. Kernel logs show the following:

Jun 29 16:31:26 kvm kernel: [ 145.888552] ------------[ cut here ]------------
Jun 29 16:31:26 kvm kernel: [ 145.888557] NETDEV WATCHDOG: p6p1 (igb): transmit queue 0 timed out
Jun 29 16:31:26 kvm kernel: [ 145.888595] WARNING: CPU: 6 PID: 0 at /build/linux-hwe-0EwvTm/linux-hwe-4.15.0/net/sched/sch_generic.c:323 dev_watchdog+0x222/0x230
Jun 29 16:31:26 kvm kernel: [ 145.888597] Modules linked in: vfio_pci vfio_virqfd vfio_iommu_type1 vfio ebtable_filter ebtables xt_multiport openvswitch nsh nf_nat_ipv6 nf_nat_ipv4 binfmt_misc ip6t_REJECT nf_reject_ipv6 xt_hl ip6t_rt ppdev intel_rapl nf_conntrack_ipv6 nf_defrag_ipv6 x86_pkg_temp_thermal intel_powerclamp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel ipt_REJECT nf_reject_ipv4 intel_cstate usblp xt_limit xt_tcpudp ipmi_si ipmi_devintf xt_addrtype intel_rapl_perf ipmi_msghandler lpc_ich parport_pc mei_me mei pcbc shpchp ie31200_edac mac_hid aesni_intel crypto_simd glue_helper cryptd aes_x86_64 dm_crypt vhost_net vhost tap kvm_intel kvm irqbypass nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack ip6table_filter ip6_tables nf_conntrack_netbios_ns nf_conntrack_broadcast nf_nat_ftp nf_nat nf_conntrack_ftp nf_conntrack
Jun 29 16:31:26 kvm kernel: [ 145.888689] libcrc32c iptable_filter ip_tables x_tables sunrpc ib_iser rdma_cm iw_cm ib_cm ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi nct6775 hwmon_vid coretemp lp parport autofs4 btrfs xor zstd_compress raid6_pq raid1 raid10 ast ttm drm_kms_helper syscopyarea sysfillrect igb sysimgblt fb_sys_fops hid_generic dca i2c_algo_bit usbhid ahci ptp libahci drm mpt3sas pps_core hid raid_class scsi_transport_sas video
Jun 29 16:31:26 kvm kernel: [ 145.888761] CPU: 6 PID: 0 Comm: swapper/6 Not tainted 4.15.0-54-generic #58~16.04.1-Ubuntu
Jun 29 16:31:26 kvm kernel: [ 145.888763] Hardware name: ASUSTeK COMPUTER INC. P9D-C Series/P9D-C Series, BIOS 1301 01/26/2015
Jun 29 16:31:26 kvm kernel: [ 145.888770] RIP: 0010:dev_watchdog+0x222/0x230
Jun 29 16:31:26 kvm kernel: [ 145.888773] RSP: 0018:ffff8a72efd83e68 EFLAGS: 00010282
Jun 29 16:31:26 kvm kernel: [ 145.888777] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000006
Jun 29 16:31:26 kvm kernel: [ 145.888779] RDX: 0000000000000007 RSI: 0000000000000082 RDI: ffff8a72efd96490
Jun 29 16:31:26 kvm kernel: [ 145.888782] RBP: ffff8a72efd83e98 R08: 0000000000000001 R09: 000000000000049c
Jun 29 16:31:26 kvm kernel: [ 145.888785] R10: 0000000000000000 R11: 000000000000049c R12: 0000000000000008
Jun 29 16:31:26 kvm kernel: [ 145.888787] R13: ffff8a72bda80000 R14: ffff8a72bda80478 R15: ffff8a72bda79940
Jun 29 16:31:26 kvm kernel: [ 145.888791] FS: 0000000000000000(0000) GS:ffff8a72efd80000(0000) knlGS:0000000000000000
Jun 29 16:31:26 kvm kernel: [ 145.888794] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Jun 29 16:31:26 kvm kernel: [ 145.888797] CR2: 00007fa1302dbf48 CR3: 00000001f120a002 CR4: 00000000001626e0
Jun 29 16:31:26 kvm kernel: [ 145.888800] Call Trace:
Jun 29 16:31:26 kvm kernel: [ 145.888803] <IRQ>
Jun 29 16:31:26 kvm kernel: [ 145.888812] ? dev_deactivate_queue.constprop.33+0x60/0x60
Jun 29 16:31:26 kvm kernel: [ 145.888819] call_timer_fn+0x32/0x140
Jun 29 16:31:26 kvm kernel: [ 145.888824] run_timer_softirq+0x1ed/0x440
Jun 29 16:31:26 kvm kernel: [ 145.888830] ? ktime_get+0x3e/0xa0
Jun 29 16:31:26 kvm kernel: [ 145.888838] ? lapic_next_deadline+0x26/0x30
Jun 29 16:31:26 kvm kernel: [ 145.888846] __do_softirq+0xf5/0x28f
Jun 29 16:31:26 kvm kernel: [ 145.888856] irq_exit+0xb8/0xc0
Jun 29 16:31:26 kvm kernel: [ 145.888861] smp_apic_timer_interrupt+0x79/0x140
Jun 29 16:31:26 kvm kernel: [ 145.888866] apic_timer_interrupt+0x84/0x90
Jun 29 16:31:26 kvm kernel: [ 145.888868] </IRQ>
Jun 29 16:31:26 kvm kernel: [ 145.888879] RIP: 0010:cpuidle_enter_state+0xa7/0x300
Jun 29 16:31:26 kvm kernel: [ 145.888881] RSP: 0018:ffffac58031cfe60 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff11
Jun 29 16:31:26 kvm kernel: [ 145.888886] RAX: ffff8a72efda2840 RBX: 0000000000000005 RCX: 000000000000001f
Jun 29 16:31:26 kvm kernel: [ 145.888888] RDX: 0000000000000000 RSI: 0000000025bbf79e RDI: 0000000000000000
Jun 29 16:31:26 kvm kernel: [ 145.888890] RBP: ffffac58031cfe98 R08: ffff8a72efda16a4 R09: 0000000000000018
Jun 29 16:31:26 kvm kernel: [ 145.888893] R10: ffffac58031cfe30 R11: 0000000000000391 R12: 0000000000000005
Jun 29 16:31:26 kvm kernel: [ 145.888895] R13: ffff8a72efdacf00 R14: ffffffff9f371e38 R15: 00000021f77f87f8
Jun 29 16:31:26 kvm kernel: [ 145.888905] cpuidle_enter+0x17/0x20
Jun 29 16:31:26 kvm kernel: [ 145.888914] call_cpuidle+0x23/0x40
Jun 29 16:31:26 kvm kernel: [ 145.888920] do_idle+0x197/0x200
Jun 29 16:31:26 kvm kernel: [ 145.888926] cpu_startup_entry+0x73/0x80
Jun 29 16:31:26 kvm kernel: [ 145.888931] start_secondary+0x1ab/0x200
Jun 29 16:31:26 kvm kernel: [ 145.888939] secondary_startup_64+0xa5/0xb0
Jun 29 16:31:26 kvm kernel: [ 145.888942] Code: 37 00 49 63 4e e8 eb 92 4c 89 ef c6 05 a8 63 d8 00 01 e8 52 33 fd ff 89 d9 48 89 c2 4c 89 ee 48 c7 c7 c0 1e fa 9e e8 3e 3c 80 ff <0f> 0b eb c0 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48
Jun 29 16:31:26 kvm kernel: [ 145.889026] ---[ end trace 87c230fe7d27f115 ]---
Jun 29 16:31:26 kvm kernel: [ 145.889079] igb 0000:0a:00.0 p6p1: Reset adapter
Jun 29 16:31:30 kvm kernel: [ 149.681151] igb 0000:0a:00.0 p6p1: igb: p6p1 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX
Jun 29 16:31:40 kvm kernel: [ 159.964671] igb 0000:0a:00.0 p6p1: Reset adapter
Jun 29 16:31:44 kvm kernel: [ 163.669265] igb 0000:0a:00.0 p6p1: igb: p6p1 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX

This only happened on my Linux hypervisor, none of the other devices on my network exhibited this behaviour.

What troubleshooting steps did I take?

Different network cables
Using a newer kernel (4.15, I was on 4.4 to start)
Building igb drivers from Intel's website via DKMS and loading them
Using a different network card in a PCI express slot (e1000e) vs. onboard (igb)
Trying all slots on the NIC
Updating the BIOS on the ASUS server mainboard (P9D-C) to the latest available
Turning off TSO/GSO offloading on the NIC via ethtool

None of these issues resolved the error I was encountering. If I restarted the R7000, it caused the adapter to time out every time.

How did I solve it?

Disabling RX/TX Flow control on the switch caused the issue to stop happening.

Since I did not want to disable RX/TX Flow control globally, I implemented the fix by disabling auto negotiate and setting RX/TX flow control off (aka. "PAUSE" Ethernet frames) using interface(8) and ethtool on Ubuntu:

pre-up /sbin/ethtool -s $IFACE autoneg off speed 1000 duplex full
pre-up /sbin/ethtool -A $IFACE autoneg off rx off

Now my R7000 can do whatever it likes, including randomly restarting and my network connectivity continues to function on my hypervisor.

prosody websocket behind nginx reverse proxy

March 9, 2016March 9, 2016 Peter

Useful for kawai and other XMPP services behind the same URL (eg. for serving SSL traffic.)

WebSockets require HTTP/1.1, and prosody assumes traffic on TCP port 5280 is not secure (and trying to force it to starttls) thus requiring the configuration knob highlighted below.

prosody.cfg.lua

consider_websocket_secure = true

nginx.conf

map $http_upgrade $connection_upgrade {
    default upgrade;
    '' close;
}

server {
# ...
  location /xmpp-websocket {
    proxy_pass http://127.0.0.1:5280;
    proxy_buffering off;
    proxy_set_header Host $host;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
  }
}