Azure FunctionApp - Only one usage of each socket address (protocol/network address/port) is normally permitted.

Question

Hello, im receiving error:

2023-02-01T09:05:53.248 [Error] Executed 'myFunctionName' (Failed, Id=df08ed2f-fa3d-4d75-a50c-6d108707bce2, Duration=1042ms)Only one usage of each socket address (protocol/network address/port) is normally permitted.

Following answers from search engine this means port exhaustion, but there are following problems in my case:

• it was working fine up to today morning;
• traffic is very low, in example i run this function once, then second time, then third and i get error;
• i do not open ANY http connections inside.

Whole function body below (removed namespaces from snippet as these are business classes which names i do not want to share):

using System.IO;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Extensions.Http;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Logging;

namespace DummyPublishers
{
    [System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
    public static class DummyStandardRolePublisher
    {
        [FunctionName("DummyPublisher")]
        public static async Task

Answer 1

@Szymon Thanks for the details. As you are not using cosmos DB input/output binding and using Cosmos DB client library then you need to leverage the lazy pattern as documented here. Please refer to manage connection document and for cosmos DB client