Setting IP filters

IP access lists filter traffic to ClickHouse services or API keys by specifying which source addresses are permitted to connect. These lists are configurable for each service and each API key. Lists can be configured during service or API key creation, or afterward.

Configure the IP access list for your serviceWhen you create a ClickHouse Cloud service, the default setting for the IP allow list is ‘Allow from anywhere.’ We strongly recommend restricting access to specific IP addresses or ranges as soon as possible. Services set to Allow from anywhere may be periodically moved from an idle to an active state by internet crawlers and scanners that look for public IPs, which may result in unexpected costs.

Prepare

Before you begin, collect the IP addresses or ranges that should be added to the access list. Take into consideration remote workers, on-call locations, VPNs, etc. The IP access list user interface accepts individual addresses and CIDR notation. Classless Inter-domain Routing (CIDR) notation, allows you to specify IP address ranges smaller than the traditional Class A, B, or C (8, 6, or 24) subnet mask sizes. ARIN and several other organizations provide CIDR calculators if you need one, and if you would like more information on CIDR notation, please see the Classless Inter-domain Routing (CIDR) RFC.

Create or modify an IP access list

Applicable only to connections outside of PrivateLinkIP access lists only apply to connections from the public internet, outside of PrivateLink. If you only want traffic from PrivateLink, set DenyAll in IP Allow list.

IP access list for ClickHouse services

When you create a ClickHouse service, the default setting for the IP allow list is ‘Allow from anywhere.’From your ClickHouse Cloud services list select the service and then select Settings. Under the Security section, you will find the IP access list. Click on the Add IPs button.A sidebar will appear with options for you to configure:

Allow incoming traffic from anywhere to the service
Allow access from specific locations to the service
Deny all access to the service

IP access list for API keys

When you create an API key, the default setting for the IP allow list is ‘Allow from anywhere.’From the API key list, click the three dots next to the API key under the Actions column and select Edit. At the bottom of the screen you will find the IP access list and options to configure:

Allow incoming traffic from anywhere to the service
Allow access from specific locations to the service
Deny all access to the service

This screenshot shows an access list which allows traffic from a range of IP addresses, described as “NY Office range”:

Possible actions

To add an additional entry you can use + Add new IP

This example adds a single IP address, with a description of London server:

Delete an existing entry

Clicking the cross (x) can deletes an entry

Edit an existing entry

Directly modifying the entry

Switch to allow access from Anywhere

This isn’t recommended, but it is allowed. We recommend that you expose an application built on top of ClickHouse to the public and restrict access to the back-end ClickHouse Cloud service. To apply the changes you made, you must click Save.

Verification

Once you create your filter confirm connectivity to a service from within the range, and confirm that connections from outside the permitted range are denied. A simple curl command can be used to verify:

Attempt rejected from outside the allow list

curl https://<HOSTNAME>.clickhouse.cloud:8443

curl: (35) error:02FFF036:system library:func(4095):Connection reset by peer

curl: (35) LibreSSL SSL_connect: SSL_ERROR_SYSCALL in connection to HOSTNAME.clickhouse.cloud:8443

Attempt permitted from inside the allow list

curl https://<HOSTNAME>.clickhouse.cloud:8443

Ok.

Limitations

Currently, IP access lists support only IPv4