Enable port 25 access in xneelo Cloud

Outbound SMTP traffic on port 25 is blocked by default in xneelo Cloud to protect against spam and abuse. See more on port 25 restrictions in xneelo Cloud

If you have a legitimate use case for sending email directly from your Cloud instance, you can request access to port 25. 

If approved, we’ll enable the Public SMTP network in your Cloud project. IP addresses on this network can send outbound traffic over port 25.

Follow the steps below to request access and enable port 25.


  • Public SMTP network

    The Public SMTP network is a dedicated network that permits outbound SMTP traffic over port 25.

    The network is not available by default. It can be enabled for approved Cloud projects on request.

    Public SMTP supports IPv4 only. It does not provide an xneelo-managed mail relay.





  • Steps to enable port 25

    To enable port 25 access in your Cloud project, complete the following steps:

    1. 1
      Request access via Support.
    2. 2
      Assign an IP from the Public SMTP network to your instance.
    3. 3
      Allow outbound port 25 traffic in the security group.
    4. 4
      Configure your mail server.





  • Request access via Support

    Your request for port 25 access is subject to review. Please note that approval is not guaranteed. 

    To request access:

    1. 1
      Contact Support via Live Chat.
    2. 2
      Provide a description of what you need outbound port 25 access for, such as running a mail server or migrating an existing mail server.
    3. 3
      Wait for Support to review your request and confirm the outcome.

    Your request should be reviewed within 1 business day.

    We’ll review your request and let you know the outcome.

    If your request is approved, we’ll enable the Public SMTP network in your xneelo Cloud project.





  • Assign a Public SMTP IP to your instance

    After your request has been approved, you can use the Public SMTP network when creating a new instance or configuring an existing instance. 

    For a new instance using a random IP 

    A random IPv4 address is assigned from the Public SMTP network when you select the network during instance creation.

    1. 1
      Go to Compute > Instances.
    2. 2
      Select Launch instance.
    3. 3
      Complete the instance details.
    4. 4
      In the Networks step, select Public SMTP.
    5. 5
      Complete the remaining steps and select Launch.

    Follow the steps in Create cloud instances.

    For an existing instance using a random IP

    A random IPv4 address is assigned from the Public SMTP network when you attach the network interface. 

    1. 1
      Go to Compute > Instances.
    2. 2
      Select the instance.
    3. 3
      Open the Interfaces tab.
    4. 4
      Select Attach interface.
    5. 5
      Select the Public SMTP network.
    6. 6
      Confirm the interface attachment.

    Follow the steps in Interfaces on cloud instances.

    For an existing instance using a floating IP

    Use this option to allocate a floating IP from the Public SMTP network that can be disassociated from one instance and associated with another instance when needed.

    1. 1
      Go to Network > Floating IPs.
    2. 2
      Select Allocate Floating IP.
    3. 3
      Select the Public SMTP network.
    4. 4
      Select Allocate.
    5. 5
      The floating IP will then be allocated to your project.

    You can then associate the floating IP with your instance. 

    Follow the steps in Floating IPs in xneelo Cloud.





  • Allow outbound port 25 in the security group

    You must also enable outbound port 25 in the security group attached to your instance.

    1. 1
      Go to Network > Security Groups. 
    2. 2
      Select the security group attached to your instance.
    3. 3
      Select Manage rules.
    4. 4
      Select Add rule.
    5. 5
      Add an outbound rule with these settings:

     

    Setting Value
    Direction Outbound
    Protocol TCP
    Port 25
    Destination 0.0.0.0/0


    Use     0.0.0.0/0 when your mail server needs to connect to mail servers across the internet.

    If you use a specific SMTP relay, you can restrict the destination to the relay’s IP address.

    You do not need to add an inbound port 25 rule unless your instance must receive email directly from other mail servers.

    For more information see Create and manage security groups.





  • Configure your mail server

    After connecting your instance to the Public SMTP network, configure your mail server to send email over port 25.

    Configuring and managing your mail server is your responsibility. You remain responsible for your sending practices, mail-server security and email deliverability. See more on your responsibilities in xneelo Cloud.

    You should ensure that your mail server is securely configured and is not operating as an open relay.

    To request a PTR record, also known as reverse DNS, for your Public SMTP IP address, follow the steps in PTR – Reverse DNS.





  • Acceptable use of port 25

    We may suspend or remove access if we detect spam, abuse or other activity that could affect the reputation of our public network.

    If access is suspended or removed, the Public SMTP network and associated IP addresses may be removed from your project.

    See more in our Acceptable Use Policy.





  • Troubleshooting

    If you cannot send email over port 25:

    • Confirm that the instance is using an IPv4 address from the Public SMTP network.
    • Confirm that outbound TCP port 25 is enabled in the correct security group.
    • Confirm that your mail server is securely configured and is not operating as an open relay.
    • Check your domain’s DNS and PTR or reverse DNS configuration.
    • Confirm that you are not using an IP address from the standard Public network.

    Contact Support if Public SMTP is no longer available in your project or if an associated IP address has been removed.



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