Environment with id '4' already contains a virtual machine resource with name 'xyz'

[dazinator]

I was testing deployment of a dockerised agent (linux)
It ran fine and appeared in DevOps (Pipelines > Environments > VM Resource)
I then deleted the VM, re-created a new VM, and re-deployed the agent to the VM running as a docker container again.
The VM resource was never removed from DevOps.
However I can no longer deploy to the agent and checking its logs I see:

Environment with id '4' already contains a virtual machine resource with name 'xyz'.

Is there any way to make this agent automatically replace an agent with an existing name in devops so that is doesn't fail on startup?

[dazinator]

still no news?

[acottuli]

@dazinator I just ran into the same issue. Passing the flag --replace to ./config.sh fixed the issue for me.

From the output of ./config.sh --help

Configure options:
 --pool <pool>                     Pool name for the agent to join
 --agent <agent>                   Agent name
 --replace                         Replace the agent in a pool. If another agent is listening by that
                                   name, it will start failing with a conflict.
 --work <workDirectory>            Work directory where job data is stored. Defaults to _work under the
                                   root of the agent directory. The work directory is owned by a given
                                   agent and should not share between multiple agents.
 --acceptTeeEula                   macOS and Linux only. Accept the TEE end user license agreement.
 --gitUseSChannel                  Windows only. Tell Git to use Windows' native cert store.
 --alwaysExtractTask               Perform an unzip for tasks for each pipeline step.

If you want to dig deeper, the relevant source code can be found here

azure-pipelines-agent/src/Agent.Listener/Configuration/ConfigurationManager.cs

Lines 219 to 245 in e5dca16

	if (agent != null)
	{
	_term.WriteLine(StringUtil.Loc("AgentWithSameNameAlreadyExistInPool", agentSettings.PoolName, agentSettings.AgentName));
	if (command.GetReplace())
	{
	// Update existing agent with new PublicKey, agent version and SystemCapabilities.
	agent = UpdateExistingAgent(agent, publicKey, systemCapabilities);
	try
	{
	agent = await agentProvider.UpdateAgentAsync(agentSettings, agent, command);
	_term.WriteLine(StringUtil.Loc("AgentReplaced"));
	break;
	}
	catch (Exception e) when (!command.Unattended())
	{
	_term.WriteError(e);
	_term.WriteError(StringUtil.Loc("FailedToReplaceAgent"));
	}
	}
	else if (command.Unattended())
	{
	// if not replace and it is unattended config.
	agentProvider.ThrowTaskAgentExistException(agentSettings);
	}
	}