Network Policies¶

Overview¶

By default, Snowflake allows users to connect to the service from any computer or device IP address. A security administrator (or higher) can create a network policy to allow or deny access to a single IP address or a list of addresses. Network policies currently support only Internet Protocol version 4 (i.e. IPv4) addresses.

An administrator with sufficient permissions can create any number of network policies. A network policy is not enabled until it is activated at the account or individual user level. To activate a network policy, modify the account or user properties and apply the network policy to the object. Only a single network policy can be applied to the account or a specific user at a time.

A network policy can also be applied to some types of security integrations.

Creating Network Policies¶

You can create a network policy using Snowsight, the Classic Console, or SQL:

Snowsight

1. Click Admin » Security » Network Policies.

2. Click the + Network Policy button in the top-right corner of the page. The New network policy dialog opens.

3. Specify the following properties:

   Property	Description
   Policy Name	Identifier for the network policy; must be unique for your account. The identifier must start with an alphabetic character and cannot contain spaces or special characters unless the entire identifier string is enclosed in double quotes (e.g. "My object"). Identifiers enclosed in double quotes are also case-sensitive. For more details, see Identifier requirements.
   Allowed IP Addresses	Comma-separated list of one or more IPv4 addresses that are allowed access to your Snowflake account. This is referred to as the allowed list. Snowflake automatically blocks all IP addresses not included in the allowed list. Each IP address can cover a range of addresses using Classless Inter-Domain Routing (CIDR) notation. For information, see CIDR Notation (in this topic). For examples, see Examples of Allowed / Blocked Address Lists (in this topic).
   Blocked IP Addresses	Comma-separated list of one or more IPv4 addresses that are denied access to your Snowflake account. This is referred to as the blocked list. Set this parameter only when you are allowing access to a range of IP addresses in the Allowed IP Addresses list and want to deny access to one or more IP addresses within the range. Each IP address can cover a range of addresses using Classless Inter-Domain Routing (CIDR) notation. For information, see CIDR Notation (in this topic). For examples, see Examples of Allowed / Blocked Address Lists (in this topic).
   Comment	Specifies a comment for the network policy.

4. Click the Create network policy button.

Classic Console

1. Click Account » Policies. The Policies page appears.

2. Click the Create button. The Create Network Policy dialog appears.

3. In the Name field, enter a name for the network policy.

4. In the Allowed IP Addresses field, enter one or more IPv4 addresses that are allowed access to this Snowflake account, separated by commas.

   Note

   To block all IP addresses except for a set of specific addresses, you only need to define an allowed IP address list. Snowflake automatically blocks all IP addresses not included in the allowed list.

5. In the Blocked IP Addresses field, optionally enter one or more IPv4 addresses that are denied access to this Snowflake account, separated by commas. Note that this field is not required and is used primarily to deny specific addresses in a range of addresses in the allowed list.

   Caution

   • When a network policy includes values in both the allowed and blocked IP address lists, Snowflake applies the blocked IP address list first.

   • Do not add 0.0.0.0/0 to the blocked IP address list. 0.0.0.0/0 is interpreted to be “all IPv4 addresses on the local machine”. Because Snowflake resolves this list first, this would block your own access. Also, note that it is not necessary to include this IP address in the allowed IP address list.

6. Enter other information for the network policy, as needed, and click Finish.

SQL

Execute a CREATE NETWORK POLICY statement.

Viewing Network Policies¶

View information about the network policies through Snowsight, the Classic Console, or using SQL:

Snowsight

Select Admin » Security » Network Policies » <policy_name>.

Classic Console

Click Account » Policies » <policy_name>.

SQL

Execute one of the following statements:

• SHOW NETWORK POLICIES

• DESCRIBE NETWORK POLICY

Activating a Network Policy for Your Account¶

To enforce a network policy for all users in your Snowflake account, activate the network policy for your account.

Once the policy is associated with your account, Snowflake restricts access to your account based on the allowed IP address list and blocked IP address list. Any user who attempts to log in from an IP address restricted by the rules is denied access. In addition, when a network policy is associated with your account, any restricted users who are already logged into Snowflake are prevented from executing further queries.

A security administrator (or higher) can create multiple network policies; however, only one network policy can be associated with an account at any one time. Associating a network policy with your account automatically removes the currently-associated network policy (if any).

Note that your current IP address must be included in the allowed IP addresses list in the policy. Otherwise, when you activate the policy, Snowflake returns an error. In addition, your current IP address cannot be included in the blocked IP addresses list.

You can associate a network policy with your account using Snowsight, the Classic Console, or SQL:

Snowsight

1. Click Admin » Security » Network Policies.

2. Click the Activate Policy button to the right of the policy that you are activating.

Classic Console

1. Click Account » Policies.

2. Click on a policy to select it and populate the side panel on the right.

3. Click the Activate button in the right panel.

SQL

Execute an ALTER ACCOUNT statement that sets the network policy using the NETWORK_POLICY account parameter.

Activating Network Policies for Individual Users¶

To enforce a network policy for an specific user in your Snowflake account, activate the network policy for the user. Only a single network policy can be activated for each user at a time; however, different network policies can be activated for different users for granular control. Associating a network policy with a user automatically removes the currently-associated network policy (if any).

Once the policy is associated with the user, Snowflake restricts access to the user based on the allowed IP address list and blocked IP address list. If the user with an activated user-level network policy attempts to log in from an IP address restricted by the rules, the user is denied access to Snowflake.

In addition, when a user-level network policy is associated with the user and the user is already logged into Snowflake, if the user’s IP address does not match the user-level network policy rules, Snowflake prevents the user from executing further queries.

To activate a network policy for an individual user, set the NETWORK_POLICY parameter for the user using ALTER USER.

Modifying Network Policies¶

Network policies can be modified through Snowsight, the Classic Console, or SQL, specifically to add or remove IP addresses from the list of allowed and blocked addresses.

For descriptions of the network policy properties, see Creating Network Policies (in this topic).

Snowsight

1. Click Admin » Security » Network Policies.

2. Click the actions (…) button in the row for a network policy » Edit Policy. The Edit Policy dialog opens.

3. Edit any of the properties.

4. Click the Save changes button.

Classic Console

1. Click Account » Policies.

2. Click on a policy to select it and populate the side panel on the right.

3. Click the Edit button in the right panel.

4. Modify the fields as necessary:

   • To remove an IP address from the Allowed IP Addresses or Blocked IP Addresses list, click the x next to the entry.

   • To add an IP address to either list, enter one or more comma-separated IPv4 addresses in the appropriate field, and click the Add button.

5. Click Save.

SQL

Execute an ALTER NETWORK POLICY statement.

Identifying a Network Policy Activated at the Account or User Level¶

To determine whether a network policy is set on your account or for a specific user, execute the SHOW PARAMETERS command.

Account

SHOW PARAMETERS LIKE 'network_policy' IN ACCOUNT;

Copy

User

SHOW PARAMETERS LIKE 'network_policy' IN USER <username>;

Copy

For example:

SHOW PARAMETERS LIKE 'network_policy' IN USER jsmith;

Copy

Working with Network Rules¶

While restrictions on incoming requests to Snowflake are ultimately applied to an account or user with a network policy, the administrator can organize these restrictions using network rules, which are schema-level objects.

Each network rule groups together the identifiers for a particular type of request origin. For example, one network rule might include all of the IPv4 addresses that should be allowed to access Snowflake while another groups together all of the private endpoints that should be blocked.

A network rule, however, does not specify whether it is allowing or blocking the origin of a request. It simply organizes related origins into a logical unit. Administrators specify whether that unit should be allowed or blocked when they create or modify a network policy.

The general workflow is:

1. Create a network rule for a particular type of network identifier and purpose.

2. Add that network rule to the allowed rules list or blocked rules list of a network policy.

3. Apply the network policy to an account, user, or security integration.

CREATE NETWORK RULE block_public_access
  MODE = INGRESS
  TYPE = IPV4
  VALUE_LIST = ('0.0.0.0/0');

CREATE NETWORK RULE allow_vpceid_access
  MODE = INGRESS
  TYPE = AWSVPCEID
  VALUE_LIST = ('vpce-0fa383eb170331202');

CREATE NETWORK POLICY allow_vpceid_block_public_policy
  ALLOWED_NETWORK_RULE_LIST = ('allow_vpceid_access')
  BLOCKED_NETWORK_RULE_LIST=('block_public_access');

USE ROLE ACCOUNTADMIN;
ALTER ACCOUNT SET ENFORCE_NETWORK_RULES_FOR_INTERNAL_STAGES = true;

GRANT USAGE ON DATABASE securitydb TO ROLE network_admin;
GRANT USAGE ON SCHEMA securitydb.myrules TO ROLE network_admin;
GRANT CREATE NETWORK RULE ON SCHEMA securitydb.myrules TO ROLE network_admin;
USE ROLE network_admin;

CREATE NETWORK RULE cloud_network TYPE = IPV4 VALUE_LIST = ('47.88.25.32/27');

CREATE NETWORK RULE corp_network TYPE = AWSVPCEID VALUE_LIST = ('vpce-123abc3420c1931');
CREATE NETWORK RULE cloud_network TYPE = IPV4 VALUE_LIST = ('47.88.25.32/27');

CREATE NETWORK POLICY account_policy ALLOWED_NETWORK_RULE_LIST = ( 'corp_network', 'cloud_network' );

ALTER NETWORK POLICY my_policy SET BLOCKED_NETWORK_RULE_LIST = ( 'other_network' );

ALTER NETWORK POLICY my_policy ADD ALLOWED_NETWORK_RULE_LIST = ( 'new_rule' );

ALTER NETWORK POLICY my_policy REMOVE BLOCKED_NETWORK_RULE_LIST = ( 'other_network' );