--- title: "Delisting blocklisted IP addresses" description: "Blocklisting — also known as blacklisting, or being listed on a Realtime Blackhole List (RBL) — is a spam-fighting measure applied to IP addresses or ranges to" url: https://docs.us.ovhcloud.com/en/network/additional-ip/blocklist-ip-delist lang: en --- > For AI agents: the complete documentation index is available at https://docs.us.ovhcloud.com/en/llms.txt, the full documentation bundle is available at https://docs.us.ovhcloud.com/en/llms-full.txt. # Delisting blocklisted IP addresses Blocklisting — also known as blacklisting, or being listed on a Realtime Blackhole List (RBL) — is a spam-fighting measure applied to IP addresses or ranges to block email that is considered spam or may contain malware. When an email domain or IP address is blocklisted, messages sent from it may not reach their recipients, which impacts deliverability and sender reputation. Messages that are delivered may land in the recipient's spam folder rather than their inbox. Blocklists can include domain names and IP addresses that pose no actual threat. Some spam-filtering services, such as SpamRATS, also take reverse DNS into account when evaluating IP addresses. **Warning:** **NOTE:** The information in this guide is subject to change and applies to newly purchased IP addresses. OVHcloud cannot be held responsible for the actions of third-party providers. **Note:** For the best practices on running an email server, refer to our [How to prevent your emails from being marked as spam](https://docs.us.ovhcloud.com/en/bare-metal-cloud/dedicated-servers/mail-sending-optimization.md) guide.   ### Supported providers **Warning:** **NOTE:** Please review the Spamhaus blocklists closely as not all require OVHcloud US intervention; some just require the customer to properly configure the CSS. - #### [Spamhaus Block List (SBL)](https://www.spamhaus.org/lookup/) **Note:** This is for newly purchased IPs. If the IP is listed under the Spamhaus Blocklist (SBL), you will need to submit a ticket to OVHcloud US Customer Support. Support will contact our Abuse Team, who will then contact the Internet Service Provider. - #### [eXploits Block List (XBL) or Combined Spam Sources (CSS)](https://check.spamhaus.org/) If your IP is listed under eXploits Blocklist (XBL) and/or Combined Spam Sources (CSS), it is usually due to configuration issues. Please follow the steps described on the Spamhaus website to delist the IP (see the example below). Once you have followed the steps, you can delist it yourself. #### Example: - #### [Spamcop](https://www.spamcop.net/bl.shtml) On this page, you can check the current status of an IP. The SpamCop Blocking List (SCBL) is time-based: an IP is delisted automatically once spam reports stop, so there is usually no manual removal request to submit. - #### [Barracuda](https://www.barracudacentral.org/lookups) To request removal from the Barracuda Reputation Block List (BRBL), submit the [Barracuda removal request form](https://www.barracudacentral.org/rbl/removal-request). Listings are manually verified, so removal is not immediate. - #### [SpamRATS](https://spamrats.com/lookup.php) To delist an IP from SpamRATS, the first and most important step is to configure reverse DNS (rDNS). Without a valid rDNS, the UP cannot be removed from the blocklist, especially for "Worst Offender" alerts. **Step 1 - Configure rDNS** Use your external domain registrar to create an A record that maps the domain name to your server's IP address (e.g., Domain: `mail.example.com`). Configure the PTR (rDNS) record using the OVHcloud Control Panel ([instructions](https://docs.us.ovhcloud.com/en/network/dns/configure-reverse-dns.md)) or OVHcloud API ([instructions](https://docs.us.ovhcloud.com/en/network/dns/configure-reverse-dns-ovhcloud-api.md)). Use the command below or an online tool like [MXToolBoox](https://mxtoolbox.com/) to verify the rDNS is set up correctly. ``` dig -x ``` #### Good rDNS example output: ``` {{;; ANSWER SECTION: 1.2.0.192.in-addr.arpa. 300 IN PTR mail.example.com.}} ``` The IP 192.0.2.1 resolves to mail.example.com, showing a valid reverse DNS configuration. #### Bad rDNS example output: ``` {{;; ANSWER SECTION: (missing) ;; status: NXDOMAIN}} ``` No PTR record exists for 203.0.113.1, as indicated by the missing **ANSWER SECTION** and status: **NXDOMAIN**. **Step 2 - Delist an IP** Use the [SpamRATS Lookup Tool](https://www.spamrats.com/lookup.php) to check if the IP is listed. Request delisting from **basic blocklists** using the SpamRATS Removal Form. Request delisting from **Worst Offender Alerts** using the SpamRATS Contact Form and include: 1. Evidence of a valid rDNS configuration (e.g., `dig -x` output). 2. An explanation of the IP's history, ownership, and intended use. **Note:** **Best practices:** Always configure rDNS by setting up an A record at your domain registrar using the OVHcloud Control Panel ([instructions](https://docs.us.ovhcloud.com/en/network/dns/configure-reverse-dns.md)) or OVHcloud API ([instructions](https://docs.us.ovhcloud.com/en/network/dns/configure-reverse-dns-ovhcloud-api.md)). By following these steps, you can ensure proper reverse DNS setup and successfully delist your IP from SpamRATS.   ### Unsupported #### s5h.net ##### More information... To request removal, visit [the usenix RBL removal page](http://www.usenix.org.uk/content/rblremove) from the IP address that has been blocklisted. You should be delisted immediately. You can also do this using _telnet_, _curl_, or _wget_. To delist your IPv4 address using curl, log in to the listed mail server and run: ``` curl -4 http://www.usenix.org.uk/content/rblremove ``` To do just the same using _telnet_ from a Windows/Linux host, enter the _GET_ and _Host_ lines after the _telnet_ command as shown below). ``` telnet www.usenix.org.uk 80 GET /content/rblremove HTTP/1.1 Host: www.usenix.org.uk # press enter twice ``` A detailed explanation is mentioned on the site [http://www.usenix.org.uk/content/rbl.html](http://www.usenix.org.uk/content/rbl.html) #### UCEprotect ##### More information... UCEprotect periodically places large numbers of ASNs on its level-3 blocklist, and the OVHcloud ASN (AS16276) may be affected. To view the list of other affected ASNs and the number of new ASNs added, check the following links: - [http://www.uceprotect.net/en/l3charts.php](http://www.uceprotect.net/en/l3charts.php)\ [http://stats.uceprotect.net/?page=su](http://stats.uceprotect.net/?page=su) Our Abuse Team contacts UCEprotect to request the removal of our ASN from the blocklist. UCEprotect requires the network operators of the blocked ASNs to pay for express delisting. Like all major providers, OVHcloud does not pay for blocklist delisting, as it is a service outside of our control. Paying for delisting only increases blocklisting overall and ultimately harms the industry. UCEprotect states that it automatically delists ASNs after one week. As this is outside of our control, we cannot provide any guarantees in this regard. If you are currently affected by this, we recommend the following: 1. Use IPv6 addresses to send emails. UCEprotect does not blocklist email sent via IPv6. All OVHcloud services include at least one IPv6 address that you can configure, and all major email providers now support IPv6. 2. Ask the recipient to contact their email provider and request that they stop using the UCEprotect blocklist. #### Fabel Spamsources ##### More information... To delist an IP from Fabel Spamsource, navigate to their [delisting page](https://www.spamsources.fabel.dk/delist). Click `Please login to continue`, enter your email address, and check your email inbox. Use the verification code to finish logging in. Enter your IP address, provide a reason for the removal request, and click `Submit Query`. Delisting should take between 20 and 30 minutes to complete. #### MIPSpace ##### More information... To [delist an IP from MIPSpace](https://www.mipspace.com/removal.php), configure the IP with the following information: - User update rwhois of the IP - Update rwhois - Update organization on the IP - Update PTR record associated with the IP **Warning:** **NOTE:** At this time it is not possible to do this with a /32 IP block due to OVHcloud's limitation noted in [this guide](https://docs.us.ovhcloud.com/en/network/additional-ip/add-arin-organization-ip.md).   ## Go further Browse all the [Additional IP guides](https://docs.us.ovhcloud.com/en/network/additional-ip/landing-page-additional-ip.md). Browse the rest of the [OVHcloud US documentation](https://docs.us.ovhcloud.com/en/index.md) for guides on our other products and services. Learn more about [Additional IP](https://us.ovhcloud.com/network/additional-ip/) on the OVHcloud US website.