(2025.12 ‐ 2026.03) RHEL and Ubuntu VDI login fails due to EFS mount failure

Users are unable to log in to RHEL8, RHEL9, Ubuntu 22.04 and Ubuntu 24.04 VDI sessions. During instance bootstrap, the amazon-efs-utils package fails to build due to an incompatibility between the Rust version provided by Ubuntu's package repositories and the newer Cargo.lock format required by efs-utils. As a result, EFS filesystems, including the shared /home directory, are not mounted, and desktop sessions terminate immediately upon login.

As shown in the VDI installation logs at /root/bootstrap/logs/install.log.{timestamp}:

• For RHEL,

Either upgrade rustc or select compatible dependency versions with
`cargo update <name>@<current-ver> --precise <compatible-ver>`
where `<compatible-ver>` is the latest version supporting rustc 1.88.0

error: Bad exit status from /var/tmp/rpm-tmp.Fvv8Il (%build)


RPM build errors:
    Bad exit status from /var/tmp/rpm-tmp.Fvv8Il (%build)
make: *** [Makefile:56: rpm-only] Error 1
+ yum -y install 'build/amazon-efs-utils*rpm'

• For Ubuntu,

+ cargo build --release --manifest-path /root/bootstrap/latest/efs-utils/src/proxy/Cargo.toml
error: failed to parse lock file at: /root/bootstrap/latest/efs-utils/src/proxy/Cargo.lock
+ apt install -y './build/amazon-efs-utils*deb'
E: Unsupported file ./build/amazon-efs-utils*deb given on commandline

2025.12 - 2026.03

1. Create an S3 bucket with ACLs disabled.
2. Download patch_host.py and res-installation-scripts-*.tar.gz by replacing <output-directory> with the directory to download the patch script, <environment-name> with the name of your RES environment, <bucket-name> with the name of a ACLs disabled S3 bucket under the account/region where RES is deployed, RES_VERSION with 2025.12, 2025.12.01, or 2026.03 in the command below, and <partition> with Classic or GovCloud :
   1. The patch applies to 2025.12, 2025.12.01, 2026.03
   2. The patch script requires AWS CLI v2, Python 3.12.11 or above, and Boto3.
   3. Configure the AWS CLI for the account / region where RES is deployed, and make sure that you have S3 permissions to write to the bucket provided through <bucket-name>.

   4.  OUTPUT_DIRECTORY=<output-directory>
       ENVIRONMENT_NAME=<environment-name>
       RES_VERSION=<RES_VERSION>
       BUCKET_NAME=<bucket-name>
       PARTITION=<partition>
       
       mkdir -p ${OUTPUT_DIRECTORY}
       HASH=$(case $RES_VERSION in "2026.03") echo af2c97c4;; "2025.12.01") echo 8ab7b322;; "2025.12") echo 5ddacb12;; esac)
       curl https://research-engineering-studio-us-east-1.s3.us-east-1.amazonaws.com/releases/${RES_VERSION}/patch_scripts/patch_host.py --output ${OUTPUT_DIRECTORY}/patch_host.py
       curl https://research-engineering-studio-us-east-1.s3.us-east-1.amazonaws.com/releases/${RES_VERSION}/patch_scripts/patches/res-installation-scripts-${HASH}.tar.gz --output ${OUTPUT_DIRECTORY}/res-installation-scripts-${HASH}.tar.gz
      

3. Run the following patch command:

    python3 ${OUTPUT_DIRECTORY}/patch_host.py --environment-name ${ENVIRONMENT_NAME} --module installation --zip-file ${OUTPUT_DIRECTORY}/res-installation-scripts-${HASH}.tar.gz --s3-bucket ${BUCKET_NAME} --partition ${PARTITION}
   

4. Launch new Ubuntu VDIs with this fix.

1. Bake new RES-ready VDI AMIs following the Configure RES-ready AMIs documentation. In the DownloadRESLinuxInstallPackage step, replace the source with the patched script associated with your RES version:

s3://research-engineering-studio-us-east-1/releases/{RES_VERSION}/patch_scripts/patches/res-installation-scripts-{HASH}.tar.gz. Where {HASH} is af2c97c4 for 2026.03, 8ab7b322 for 2025.12.01, and 5ddacb12 for 2025.12. The step should look like the following:

1.
  - name: DownloadRESLinuxInstallPackage
            action: S3Download
            onFailure: Abort
            maxAttempts: 3
            inputs:
              - source: "s3://research-engineering-studio-us-east-1/releases/{RES_VERSION}/patch_scripts/patches/res-installation-scripts-{HASH}.tar.gz"
                destination: "/root/bootstrap/res-installation-scripts/res-installation-scripts.tar.gz"