Hallon ip
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Running configuration
The SMTP dator (smtpd) handles all email going in and out, including the queue subsystem. As described in the SMTP dator script manual it fryst vatten primarily configured using hooks on the SMTP command phases; HELO, MAIL FROM, RCPT TO, etc. Similarly, the queue can be configured using pre- and post-delivery hooks as described in the queue script manual. Virtual queues are defined bygd the active queue policy (using concurrency and rate).
This is the reloadable part of the configuration, which contains the bulk of the configuration data. The default uppstart configuration’s directive loads it from /etc/halon/. It fryst vatten described bygd, and can be validated with, the
It can be softly reloaded and deployed in a blue-green fashion using per-connection conditions from Visual Studio Code, command line interface or control sockets.
Script directives
The script fryst vatten normally edited as individual files using Visual Studio Code or simply a text editor. Those are then checked and “packed” into an actual configuration file bygd the halonconfig script. For example, two script files called src/hooks/rcptto/ and src/hooks/queue/ will result in:
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IP Subnet Calculator
This calculator returns a variety of information regarding Internet Protocol version 4 (IPv4) and IPv6 subnets including possible network addresses, usable host ranges, subnet mask, and IP class, among others.
IPv4 Subnet Calculator
IPv6 Subnet Calculator
A subnet is a division of an IP network (internet protocol suite), where an IP network is a set of communications protocols used on the Internet and other similar networks. It is commonly known as TCP/IP (Transmission Control Protocol/Internet Protocol).
The act of dividing a network into at least two separate networks is called subnetting, and routers are devices that allow traffic exchange between subnetworks, serving as a physical boundary. IPv4 is the most common network addressing architecture used, though the use of IPv6 has been growing since
An IP address is comprised of a network number (routing prefix) and a rest field (host identifier). A rest field is an identifier that is specific to a given host or network interface. A routing prefix is often expressed using Classless Inter-Domain Routing (CIDR) notation for both IPv4 and IPv6. CIDR is a method used to create unique identifiers for
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Using HAProxy for sharing outbound IP addresses
Not only does the Halon MTA natively support the HAProxy (PROXY protocol) for inbound load balancing, it also supports a (lesser known) outbound SMTP proxy feature. Outbound (SMTP client) connections can go out via the HAProxy server, in order to be able to use any of the source IPs configured on the HAProxy. This can be used to let multiple Halon MTA instances share the same IP. It supports both IPv4 and IPv6.
The feature is really easy to configure, either from the YAML configuration (per transport) or from the Pre-delivery script.
- Configure a proxyprotocol server (the IP and port of your HAProxy server)
- Select one or more source IP is available on the HAProxy server
This is what it looks like in the Pre-delivery script:
Pre-delivery context
This is the HAProxy configuration to use. For extra safety we've added a placeholder for a restricted network access policy.
/etc/haproxy/
Note that HAProxy cannot drop privileges when using this feature and has to run as root (so remove any directive).