# Known issues for Amazon EC2 instances running Amazon Linux 2 with AWS CloudHSM
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The following issues impact AWS CloudHSM and Amazon EC2 instances that are running on Amazon Linux 2.

## Issue: Amazon Linux 2 version 2018.07 uses an updated `ncurses` package (version 6) that is currently incompatible with the AWS CloudHSM SDKs
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You see the following error returned upon running the AWS CloudHSM [cloudhsm\$1mgmt\$1util](cloudhsm_mgmt_util.md) or [key\$1mgmt\$1util](key_mgmt_util.md):

```
/opt/cloudhsm/bin/cloudhsm_mgmt_util: error while loading shared libraries: libncurses.so.5: cannot open shared object file: No such file or directory
```
+ **Impact: **Instances running on Amazon Linux 2 version 2018.07 will be unable to use *all* AWS CloudHSM utilities. 
+ **Workaround: ** Issue the following command on your Amazon Linux 2 EC2 instances to install the supported `ncurses` package (version 5):

  ```
  sudo yum update && yum install ncurses-compat-libs
  ```
+ **Resolution status:** This issue has been resolved in the AWS CloudHSM client 1.1.2 release. You must upgrade to this client to benefit from the fix.