If someone is interested here is the solution via automation script:

using Skyline.DataMiner.Automation;

namespace CiscoIFInterval
{
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Globalization;
using System.Linq;
using System.Text;
using Skyline.DataMiner.Automation;
using Skyline.DataMiner.Net.ReportsAndDashboards;

/// <summary>
/// Represents a DataMiner Automation script.
/// </summary>
public class Script
{
/// <summary>
/// The script entry point.
/// </summary>
/// <param name="engine">Link with SLAutomation process.</param>
public void Run(IEngine engine)
{
try
{
engine.Timeout = TimeSpan.FromMinutes(90);
RunSafe(engine);
}
catch (ScriptAbortException)
{
// Catch normal abort exceptions (engine.ExitFail or engine.ExitSuccess)
throw; // Comment if it should be treated as a normal exit of the script.
}
catch (ScriptForceAbortException)
{
// Catch forced abort exceptions, caused via external maintenance messages.
throw;
}
catch (ScriptTimeoutException)
{
// Catch timeout exceptions for when a script has been running for too long.
throw;
}
catch (InteractiveUserDetachedException)
{
// Catch a user detaching from the interactive script by closing the window.
// Only applicable for interactive scripts, can be removed for non-interactive scripts.
throw;
}
catch (Exception e)
{
engine.ExitFail("Run|Something went wrong: " + e);
}
}

private void RunSafe(IEngine engine)
{
var start = DateTime.Now;       // (3) runtime measurement
int changedCount = 0;           // (1) count number of changed ports
int errorCount = 0;             // (2) count number of errors

Element[] elementsCISCO = engine.FindElementsByProtocol("CISCO Manager", "Production");
var activeElements = (elementsCISCO ?? Array.Empty<Element>())
.Where(x => x != null && x.IsActive)
.ToArray();

int total = activeElements.Length;
engine.GenerateInformation("START CISCO: " + total);

if (total == 0)
{
var durationEmpty = (DateTime.Now - start).TotalSeconds;
engine.GenerateInformation($"END CISCO (no active elements) – Duration: {durationEmpty:F1}s");
return;
}

int processed = 0;

foreach (Element e in activeElements)
{
processed++;
engine.GenerateInformation($"[{processed}/{total}] CISCO Switch: {e.ElementName}");

string[] displayKeys;
string[] primaryKeys;

try
{
displayKeys = e.GetTableDisplayKeys(11000);
primaryKeys = e.GetTablePrimaryKeys(11000);
}
catch (Exception ex)
{
errorCount++;
engine.GenerateInformation($"Error retrieving table keys for {e.ElementName}: {ex.Message}");
continue;
}

if (displayKeys == null || primaryKeys == null || displayKeys.Length == 0)
{
engine.GenerateInformation($"No rows found in table 11000 for {e.ElementName}");
continue;
}

// Map DisplayKey -> PrimaryKey
var keyMap = new Dictionary<string, string>(displayKeys.Length);
for (int idx = 0; idx < displayKeys.Length; idx++)
{
var dk = displayKeys[idx];
var pk = primaryKeys[idx];
if (!string.IsNullOrEmpty(dk) && !string.IsNullOrEmpty(pk))
keyMap[dk] = pk;
}

foreach (string displayKey in displayKeys)
{
if (string.IsNullOrEmpty(displayKey))
continue;

if (!keyMap.TryGetValue(displayKey, out var primaryKey) || string.IsNullOrEmpty(primaryKey))
{
engine.GenerateInformation($"WARN: No PrimaryKey found for '{displayKey}' @ {e.ElementName}");
continue;
}

try
{
var ifType = Convert.ToString(e.GetParameter(11203, displayKey)); // safe read using DisplayKey
if (ifType != "6")
continue; // only apply to ethernetCsmacd

var current = Convert.ToString(e.GetParameter(11274, displayKey)); // safe null/DBNull read

if (current != "5")
{
e.SetParameterByPrimaryKey(11274, primaryKey, 5.0);
changedCount++;
engine.GenerateInformation($"Set 11274=5.0 @ {e.ElementName}, Port '{primaryKey}' (DisplayKey='{displayKey}', previous='{current}')");

// small delay between sets to avoid device overload
System.Threading.Thread.Sleep(100);
}
}
catch (Exception ex)
{
errorCount++;
engine.GenerateInformation($"ERROR setting value @ {e.ElementName}, Row '{displayKey}' (PK='{primaryKey}'): {ex.Message}");
}
}

// optional: process only the first two switches for testing
if (processed >= 2)
break;
}

var duration = (DateTime.Now - start).TotalSeconds; // (3) runtime measurement
engine.GenerateInformation($"END CISCO – {changedCount} ports updated, {errorCount} errors, Duration: {duration:F1}s");
}
}
}