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##### SUMMARY

Our ansible.cfg lists all well-known keys, but ansible-vault fails to run if any of the keys are missing. We only publish to our CI/respective user environments keys that are appropriate for that stack. This means that an operations person cannot run ansible without having access to all known environment's keys. To us, this makes the use of multiple vault ids not all that useful.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
ansible-vault

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```
ansible 2.7.10
  config file = /Users/dkimsey/ansible/ansible.cfg
  configured module search path = ['/Users/dkimsey/ansible/library']
  ansible python module location = /Users/dkimsey/.virtualenvs/ansible-2.7/lib/python3.7/site-packages/ansible
  executable location = /Users/dkimsey/.virtualenvs/ansible-2.7/bin/ansible
  python version = 3.7.3 (default, May  1 2019, 10:48:04) [Clang 10.0.0 (clang-1000.11.45.5)]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```
DEFAULT_VAULT_IDENTITY_LIST(/Users/dkimsey/ansible/ansible.cfg) = ['qa@~/.vault-qa', 'stg@~/.vault-staging', 'prod@~/.vault-production']
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->

n/a


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```
$ echo "my-secret-key" > ~/.vault-staging
$ ansible-vault encrypt_string --vault-id=stg --name client
```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->

I'd expect it to skip missing vault keys. Maybe log it in verbose mode that it tried to access and failed.

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```
ansible-vault 2.7.10
  config file = /Users/dkimsey/ansible/ansible.cfg
  configured module search path = ['/Users/dkimsey/ansible/library']
  ansible python module location = /Users/dkimsey/.virtualenvs/ansible-2.7/lib/python3.7/site-packages/ansible
  executable location = /Users/dkimsey/.virtualenvs/ansible-2.7/bin/ansible-vault
  python version = 3.7.3 (default, May  1 2019, 10:48:04) [Clang 10.0.0 (clang-1000.11.45.5)]
Using /Users/dkimsey/ansible/ansible.cfg as config file
ERROR! The vault password file /Users/dkimsey/.vault-qa was not found
```

options = context.CLIARGS
        
        loader = DataLoader()
        basedir = options.get('basedir', False)
        if basedir:
            loader.set_basedir(basedir)
            add_all_plugin_dirs(basedir)
            AnsibleCollectionConfig.playbook_paths = basedir
            default_collection = _get_collection_name_from_path(basedir)
            if default_collection:
                display.warning(u'running with default collection {0}'.format(default_collection))
                AnsibleCollectionConfig.default_collection = default_collection
        vault_ids = list(options['vault_ids'])
        default_vault_ids = C.DEFAULT_VAULT_IDENTITY_LIST
        vault_ids = default_vault_ids + vault_ids
        vault_secrets = CLI.setup_vault_secrets(loader,
                                                vault_ids=vault_ids,
                                                vault_password_files=list(options['vault_password_files']),
                                                ask_vault_pass=options['ask_vault_pass'],
                                                auto_prompt=False)
        loader.set_vault_secrets(vault_secrets)
        
        inventory = InventoryManager(loader=loader, sources=options['inventory'])
        
        
        variable_manager = VariableManager(loader=loader, inventory=inventory, version_info=CLI.version_info(gitinfo=False))
        return loader, inventory, variable_manager
    @staticmethod
    def get_host_list(inventory, subset, pattern='all'):