How To Fix RT251 - LAN -- Number of collisions

SAP Error Message - Details

• Message type: E = Error

• Message class: RT - Monitoring infrastructure MSG and alert texts

• Message number: 251

• Message text: LAN -- Number of collisions

What causes this issue?

A collision in a LAN occurs when two stations both try to transport a
packet on the same channel at the same time, which leads to the
destruction of both data packets - they must therefore be sent again.

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

INCLUDE BC_MONI_LAN OBJECT DOKU ID TX LANGUAGE EN
In the case of a Token Ring Architecture, <LS>Collisions per Second</>
is missing.
For more information about the LAN, select the node and choose
<LS>Start Analysis Method</>.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message RT251 - LAN -- Number of collisions ?

  The SAP error message RT251, which indicates "LAN -- Number of collisions," typically relates to network issues, particularly in environments where SAP systems are communicating over a Local Area Network (LAN). This error suggests that there are multiple collisions occurring on the network, which can lead to performance degradation and connectivity issues.
  Causes:
  
  Network Congestion: High traffic on the network can lead to packet collisions, especially in shared network environments.
  Faulty Network Hardware: Malfunctioning network devices (like switches, routers, or network interface cards) can cause increased collisions.
  Improper Network Configuration: Misconfigured network settings, such as duplex mismatches (half-duplex vs. full-duplex), can lead to collisions.
  Cable Issues: Damaged or low-quality network cables can also contribute to increased collision rates.
  Excessive Broadcast Traffic: Too many broadcast packets can saturate the network, leading to collisions.
  
  Solutions:
  
  Network Analysis: Use network monitoring tools to analyze traffic and identify congestion points or faulty devices.
  Upgrade Network Hardware: If the network devices are outdated or malfunctioning, consider upgrading to newer, more efficient hardware.
  Check Configuration: Ensure that all network devices are properly configured, particularly regarding duplex settings. Both ends of a connection should match (both should be full-duplex or both should be half-duplex).
  Reduce Broadcast Traffic: Implement VLANs or other network segmentation techniques to reduce unnecessary broadcast traffic.
  Replace Cables: Inspect and replace any damaged or low-quality network cables.
  Increase Bandwidth: If the network is consistently congested, consider increasing the bandwidth or capacity of the network.
  
  Related Information:
  
  Monitoring Tools: Tools like Wireshark, SolarWinds, or PRTG can help monitor network traffic and identify issues.
  Network Topology: Understanding the network layout can help in diagnosing where collisions are occurring.
  SAP Notes: Check SAP's support portal for any specific notes or patches related to network performance issues.
  Documentation: Review the documentation for your network hardware to ensure optimal configuration and performance.
  
  By addressing the underlying causes of the collisions, you can resolve the RT251 error and improve the overall performance of your SAP system's network connectivity.