Problem installing AWS Elastic Disaster Recovery Agent on Linux

I am following the "Upgrading from CEDR to AWS DRS" instructions.

I have successfully installed the agent on several machines - and got replication working.

However in one machine the install fails with "ERROR Failed to download installer".

According to the log this was retried several times with same result.

I have checked the troubleshooting guide

Disk space - 12GB free Network - can connect externally (including direct "wget" to "https://aws-drs-internal-us-west-2.s3.us-west-2.amazonaws.com")

Plus I have a near identical machine - same kernel, same memory, same network connectivity - on which this has worked.

Any ideas gratefully received.

Log detail

2024-03-14 17:03:39,367 ERROR      Failed to download installer, retrying
Traceback (most recent call last):
  File "shared/installer_utils/downloads.py", line 62, in inner
  File "requests/api.py", line 75, in get
  File "requests/api.py", line 61, in request
  File "requests/sessions.py", line 529, in request
  File "requests/sessions.py", line 687, in send
  File "requests/models.py", line 838, in content
MemoryError [installation_id: cfa6cedd-f5c9-4434-bf93-4c7a2acd3960, agent_version: 5.29.0.2024.056.1027, aws_instance_id: i-0bb2cbf74a1576267, mac_addresses: 2557591013316, _origin_client_type: installer]
2024-03-14 17:03:45,191 ERROR      Failed to download installer                                                     [installation_id: cfa6cedd-f5c9-4434-bf93-4c7a2acd3960, agent_version: 5.29.0.2024.056.1027, aws_instance_id: i-0bb2cbf74a1576267, mac_addresses: 2557591013316, _origin_client_type: installer]
2024-03-14 17:03:45,196 ERROR      Failed Downloading the AWS Replication Agent
Traceback (most recent call last):
  File "dirrus/installer_shared/installer_main.py", line 424, in download_installer_files
  File "shared/installer_utils/downloads.py", line 88, in download_s3_file_with_retries
  File "shared/installer_utils/downloads.py", line 77, in inner
Exception: Failed to download installer [installation_id: cfa6cedd-f5c9-4434-bf93-4c7a2acd3960, agent_version: 5.29.0.2024.056.1027, aws_ins