Troubleshooting NiagaraNetwork Pending Subscribe / Unsubscribed

[RandyDavis]

Issue

NiagaraNetwork point subscriptions get stuck constantly reporting 'Pending Subscribe' or are 'unsubscribed'.

Product Line

TAC IA Series

Environment

• I/A Series Jace (N4/AX)
• I/A Series Enterprise Server (Niagara Framework N4/AX)

Cause

Various configuration issues between the Jace and Enterprise sever.

Resolution

Troubleshooting 'Pending Subscribe' or 'Unsubscribed' (N4 or AX):

• Performing 'Manual Disconnect' on the Niagara Station 'Client connection' may clear this state.
  • Perform 'Manual Disconnect' on each side of the Niagara Network connection between the two stations having issues. It is possible that one side of the Fox connection might show connected on the 'Client Connection' and the other side shows disconnected for the associated 'Server Connection'. The manual disconnect clears this state.
• Check for multiple FOX services.
  • Typically there is only one service, though there are use cases for more than one. Sometimes the FOX service is mistakenly duplicated and both services then have the same ports, which is incorrect and causes problems. Use the ProgramService (Batch Editor) to look for 'custom object', 'fox', 'foxService'. Either delete the extra service(s) or edit the ports so to remove any conflicts.
• Duplicate station names can cause fox problems.
  • Look at station 'Spy', 'fox', 'log index' to see all the fox connections.
  • Look for duplicate station names that have different IP addresses. Duplicate station names can cause stations to keep getting disconnected as each station fights to be connected. Duplicate stations can be caused when an integrator connects their engineering laptop to a network and they have stations running on the laptop that were engineered for that job, thus resulting in more than one instance of a station running at once. In rare instances stations were installed multiple times at a site and not renamed before installation into the next platform.
• Fox connection getting dropped.
  • Either network issues on the LAN or duplicate stations. Or denial of service attack on the Supervisor. Wireshark can help diagnose LAN problems or have the IT person on site look at your station IP addresses. 
• Try increasing the Request Timeout and the Socket Option Timeout in the Fox Service.
  • Make Fox wait longer before timing out on messages. It is not typically needed to modify these defaults. 
• Regarding AX and N4 mix, make sure when an AX is connecting to an N4, the user in the N4 station, being used by the AX, must have the AXDigestScheme for the authentication scheme. 
  • The Cipher Suite Group setting in the Fox Service must be set to 'Supported' when connecting any AX version prior to 3.8u3 (3.8.311) to an N4 station via NiagaraNetwork.
• Make sure Provisioning is correctly configured.
  • If not being used, remove it. This might be an N4 only problem, but there have been instances encountered where a station that was converted from AX to N4 was having the 'Pending Subscribe' issue due to NiagaraProvisioning being only partially configured. Provisioning not correctly configured will cause the 'Pending Subscribe' problem