C# build with netcore2.1 failed on Linux and succed on Mac/OS

The job on Linux was running fine and suddenly stop , with the following errors:

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Installing .NET Core
$ export DOTNET_SKIP_FIRST_TIME_EXPERIENCE=1
$ export DOTNET_CLI_TELEMETRY_OPTOUT=1
7.70s0.49sE: Unable to locate package dotnet-sdk-2.1
E: Couldn’t find any package by glob ‘dotnet-sdk-2.1’
E: Couldn’t find any package by regex ‘dotnet-sdk-2.1’
The command “sudo apt-get install -qq dotnet-sdk-2.1=2.1.502*” failed and exited with 100 during .
Your build has been stopped.

The same job pass in Mac/Os
The cnfiguration is c# and netcore2.1

The .travis.yml is here:

We are still not clear on what’s triggering this failure but it seems that running your build on dist: xenial fixes it.

I’ve created this PR that you can check: https://github.com/moh-hassan/odata2poco/pull/23.

Thanks @dominic
I merged your PR and It’s working fine on xenial dist.

Glad to hear it! Sorry again for the disruption.

I’ll be closing this topic for now but don’t hesitate to open a new one if this happens again.