Lambda file-system-configs not added to function

Trying to add EFS to a Lambda but I do not see the mounts being added to the Lambda Docker container. I believe the Lambda Docker container is not getting the properties to add the mount (mount_volumes’: ) in the first place.

When trying to add the file-system-configs to the Lambda update config the command runs without issue but the data returned does not include the file-system-configs data. I know that EFS support is not complete within LocalStack but I am just curious if this is incomplete development, there is in fact a bug or I am making a mistake? Any recommendations around this would be appreciated?

Thanks in advance.


Image: localstack/localstack-pro:latest (3.4.1-dev)
Cmd: awslocal lambda update-function-configuration --function-name myFunction-fb12c3c --file-system-configs ‘[{“Arn”:“arn:aws:elasticfilesystem:ca-central-1:000000000000:access-point/fsap-3ef9cb7c”,“LocalMountPath”:“/mnt/efs”}]’
“FunctionName”: “myFunction-fb12c3c”,
“FunctionArn”: “arn:aws:lambda:ca-central-1:000000000000:function:myFunction-fb12c3c”,
“Runtime”: “python3.10”,
“Role”: “arn:aws:iam::000000000000:role/lambdaRole-d7562e0”,
“Handler”: “lambda_function.lambda_handler”,
“CodeSize”: 531,
“Description”: “”,
“Timeout”: 3,
“MemorySize”: 128,
“LastModified”: “2024-05-27T17:58:50.082977+0000”,
“CodeSha256”: “q4YhDWusQ6vsQZxaqdUaLdH+gjl7p/fZ+MWwEGXA6gg=”,
“Version”: “$LATEST”,
“VpcConfig”: {
“SubnetIds”: [
“SecurityGroupIds”: [
“VpcId”: “vpc-0c8cf350”
“TracingConfig”: {
“Mode”: “PassThrough”
“RevisionId”: “43b968c7-1691-49f4-81e6-7efa675f0104”,
“State”: “Active”,
“LastUpdateStatus”: “InProgress”,
“LastUpdateStatusReason”: “The function is being created.”,
“LastUpdateStatusReasonCode”: “Creating”,
“PackageType”: “Zip”,
“Architectures”: [
“EphemeralStorage”: {
“Size”: 512
“SnapStart”: {
“ApplyOn”: “None”,
“OptimizationStatus”: “Off”
“RuntimeVersionConfig”: {
“RuntimeVersionArn”: “arn:aws:lambda:ca-central-1::runtime:8eeff65f6809a3ce81507fe733fe09b835899b99481ba22fd75b5a7338290ec1”
“LoggingConfig”: {
“LogFormat”: “Text”,
“LogGroup”: “/aws/lambda/myFunction-fb12c3c”

Hi @mark.lindseth,

Indeed, EFS is not currently fully supported as mentioned in our docs, which means the use case involving lambda will not function. Could you kindly submit a feature request on our GitHub page to document your use case?

Thank you.