Monitoring network configuration fault

ID: fm:monitoring-network-fault
IRI: https://solarlattice.org/kb/fm/monitoring-network-fault
Status: active
Also known as: DNS server could not be resolved, Webconnect error, IP address conflict, IGMP snooping, DHCP address change, router energy-saving LAN port, datalogger offline, blocked firewall ports, datalogger network connection errors

This fault is in the network setup, not the PV hardware: the inverter or data logger cannot talk to the monitoring portal because of a network settings problem. It shows up as Webconnect errors such as no connection, or a DNS server that is not configured or could not be resolved. Sometimes the energy manager also cannot find devices on the network. Common causes are IGMP snooping on the switch, router LAN ports that shut down to save energy, and firewall rules that block the required ports. To confirm it, log into the inverter and read the Webconnect status, plus the current IP address, gateway and DNS server. To fix it, turn off IGMP snooping, stop the router from shutting down LAN ports, and open the required ports in the firewall. If DNS still fails, set a static IP address with a public DNS server, but plan it carefully so you do not create IP conflicts. On some STP50-41 firmware versions, DNS fails over LAN because of a firmware bug, and a firmware update fixes it.

<!-- review notes

sentence 3: support check: partial - IGMP snooping and the firewall are stated as causes, but router LAN ports shutting down for energy saving is not clearly stated as a cause.
sentence 5: support check: partial - IGMP snooping deactivation, not deactivating LAN ports and opening firewall ports are all stated, but energy-saving shutdown of ports is not explicitly stated.
sentence 7: support check: partial - u11 states the affected firmware versions and the fix by firmware update, but never calls the cause a firmware bug.
sentence 1: review: partial - The passages say Webconnect or portal communication errors probably come from network settings, but they never say 'not the PV hardware' and never mention data loggers, only inverters.
sentence 7: review: partial - The affected STP50-41 firmware versions, the DNS failure over LAN and the fix by firmware update are all stated, but the article never calls the cause a firmware bug. -->

Claims

`caused_by`

c1 drafted · lead IGMP snooping on switch proposed

The switch treats the SMA device as inactive, cuts its connection, and the link does not come back.

246498 sec=h451 h=b5c8afa18dff
246498 sec=h452 h=64911a47d918

c2 drafted · lead Router port energy saving proposed

The router or switch shuts down LAN ports to save energy.

246498 sec=h451 h=b5c8afa18dff
SWebBox-BA-en-36 tbl=37.r2 h=7b62eb0fafb1
259761 tbl=74.r2 h=aacc86440966

review note: support check: partial - u8 and u21 mention energy saving mode on router ports and u2 mentions LAN ports being deactivated, but none explicitly state the router/switch shuts down LAN ports to save energy as a cause (u8's cause is garbled).

c3 drafted · lead Blocked firewall ports proposed

SMA lists ports 9523 and 3478 (registrar, proxy, STUN) as the ones that must stay open.

246498 tbl=81.r1 h=b9557e0ce5a3
SBxx-US-1XP-41-BA-en-12 sec=h511 h=c3abea00d0c7
SBxx-US-1XP-41-BA-en-12 sec=h515 h=c3abea00d0c7
SBxx-US-1XP-41-BA-en-12 sec=h519 h=c3abea00d0c7

c4 drafted · lead Device firmware defect

STP50-41 on firmware 3.12.17.R and 3.12.18.R cannot resolve DNS over a LAN connection.

DNS problem when using LAN (Ethernet) with STP50-41 sec=h1 h=ad1188949ab2

`affects`

c5 drafted · lead Inverter

DNS Server could not be resolved sec=h1 h=d5f02e3ee0df
DNS problem when using LAN (Ethernet) with STP50-41 sec=h1 h=ad1188949ab2

c6 drafted · lead Monitoring data logger

44002762194-troubleshooting-s1-w4g-st-datalogger-network-connection-errors sec=h1 h=6540434b38b1
SWebBox-BA-en-36 tbl=37.r2 h=7b62eb0fafb1
SWebBox-BA-en-36 sec=6.6.2 h=dcd17c991775

review note: support check: partial - u4 and u8 show network connection problems for a datalogger/Sunny WebBox, but they don't clearly attribute them to a network configuration fault; u37 only describes DHCP.

`presents_as`

c7 drafted · lead Communication loss

The inverter cannot reach the monitoring portal.

SBxx-US-1XP-40-BA-en-13 sec=h300 h=4985b8cec05a
shpxxus20-event-messages tbl=1.r68 h=13727c830dd3
246498 sec=h451 h=b5c8afa18dff
DNS Server could not be resolved sec=h1 h=d5f02e3ee0df

c8 drafted · lead DNS resolution error proposed

Webconnect status says the DNS server could not be resolved or is not configured. The inverter web interface still works.

DNS Server could not be resolved sec=h1 h=d5f02e3ee0df
DNS problem when using LAN (Ethernet) with STP50-41 sec=h1 h=ad1188949ab2
SBxx-US-1XP-40-BA-en-13 sec=h304 h=fe65cc3718d5
shpxxus20-event-messages tbl=1.r70 h=e9a07e998a9d
SBxx-US-1XP-41-BA-en-12 sec=h517 h=1a6d2981b2b4

c9 drafted · lead Devices not detected on network proposed

The energy manager finds none, or not all, of the devices connected over Speedwire.

246498 tbl=81.r1 h=b9557e0ce5a3

`detected_by`

c10 drafted · lead Communication status check proposed

Read the Webconnect status, current IP address, gateway and DNS server in the inverter's instantaneous values.

DNS Server could not be resolved sec=h1 h=d5f02e3ee0df

`mitigated_by`

c11 drafted · lead Disable IGMP snooping proposed

246498 sec=h452 h=64911a47d918

c12 drafted · lead Disable LAN port energy saving proposed

Another option is a router port where energy saving is off by default, for example LAN 1.

246498 sec=h451 h=b5c8afa18dff
SWebBox-BA-en-36 tbl=37.r2 h=7b62eb0fafb1

review note: support check: partial - u2 says configure the LAN ports not to be deactivated and u8 says use LAN 1 where energy saving is usually disabled, though u8's wording on the cause is garbled.

c13 drafted · lead Open firewall ports proposed