Policies

Anyone using this service does so at their own volition and JAMM Consulting is not liable for any outcomes from the use and/or misuse of it.

If you disagree with this policy, do not use this service for any purposes whatsoever.

DNS Checks

Internet RFC 1912, Section 2.1 has these requirements:

Every Internet-reachable host should have a name. The consequences of this are becoming more and more obvious. Many services available on the Internet will not talk to you if you aren't correctly registered in the DNS.

Make sure your PTR and A records match. For every IP address, there should be a matching PTR record in the in-addr.arpa domain. If a host is multi-homed, (more than one IP address) make sure that all IP addresses have a corresponding PTR record (not just the first one). Failure to have matching PTR and A records can cause loss of Internet services similar to not being registered in the DNS at all.

1. If the sending server's IP address does not have a reverse DNS entry, we reject the email.
2. If the IP address we get back from doing a forward lookup on the reverse DNS entry does not match the sender's IP address, we reject the email.

Listing Procedure

Much spam comes from dynamically assigned IP addresses since the spammer can just jump to another IP address once their current IP is blocked. This gives the spammer an easy way to avoid being shut down. Also, legitimate emails sent from a dynamically assigned IP should be relayed through their ISP's mail server (which should have a static IP).

Therefore, we aim to block all dynamic IP addresses.

Unfortunately, we have no way to tell if any given IP address is dynamic or static without information from the entity that owns it.

Currently, the only reasonable way to identify dynamic IPs is by using reverse DNS. Therefore, we take the following steps when we receive spam:

If the spam comes from an IP that is static, we block the IP.

If we do not know if the IP is dynamic or static:

• We look up the reverse DNS entry for the IP.
• We add the domain from the reverse DNS to the list of blocked patterns.
• We run a query to find the abuse contact for the host name given in the reverse DNS.
• We send an email notification to the abuse contact asking them to give us their reverse DNS naming conventions for dynamic and static IPs.

If an ISP's namespace has more than 25 unresolved spam complaints, we consider them non-responsive and block all hosts in that range.

NOTE: All IPs that have a reverse DNS entry on a listed domain will remain blocked until the abuse contact responds to our inquiry. If you have a server that is blocked because the abuse contact has not given us the information requested, please work with them to give us what we need to avoid blocking innocent users.

Inquiries