is_reachable:"unknown"

[ewhent]

Can I access a list of all unique messages generated when the "is_reachable" field is marked as "unknown" in your tool? If not, do you have recommendations for efficiently capturing and categorizing these messages?

[amaury1093]

AFAIK there's no exhaustive list of all messages. I started trying to categorize them into 2 categories:

• unknown because IP is blacklisted (code)
• unknown because server needs a rDNS (code)

There might be other categories to group unknown messages, but I didn't explore them fully yet.

If the unknown message matches one of these 2 categories, the smtp field in the JSON output will describe the category IpBlacklisted or NeedsRDNS. If not, then the unknown message will end up uncategorized.

[amaury1093]

Yes, type and message are always present. Reacher then parses these 2 fields, and when they match something familiar, Reacher additionally adds a IpBlacklisted or NeedsRDNS category.

However, there are many other unknown type/message combinations that are not familiar. They require a human looking through them individually.

If someone looks at a large amount of those type/message combinations, we can potentially find a pattern (e.g. multiple similar messages). Once such pattern is found, I (or anyone else via a PR!) can add it to Reacher's pattern-matching algorithm.

[ewhent]

I appreciate your prompt response. I've been testing the tool on a set of emails that consistently generate "is_reachable" as "unknown." According to your explanation, there's a possibility that some of these should be categorized as "IpBlacklisted" or "NeedsRDNS."

However, upon reviewing the JSON output for one of the tested emails (see below), I couldn't find any indication of these specific categories.

json:

[
{
"input": "[email protected]",
"is_reachable": "unknown",
"misc": {
"is_disposable": false,
"is_role_account": false
},
"mx": {
"accepts_mail": true,
"records": [
"eu-smtp-inbound-1.mimecast.com.",
"eu-smtp-inbound-2.mimecast.com."
]
},
"smtp": {
"error": {
"type": "SmtpError",
"message": "transient: Internal resource temporarily unavailable - https://community.mimecast.com/docs/DOC-1369#451 [8QxuRhpcPp-1YEIRp4XrSA.uk201]"
}
},
"syntax": {
"address": "[email protected]",
"domain": "EMAIL.COM",
"is_valid_syntax": true,
"username": "XYZ"
}
}
]
Could you provide further insights into why this particular case didn't receive the "IpBlacklisted" or "NeedsRDNS" categorization? I want to ensure I'm interpreting the output correctly and contribute effectively to the tool's improvement.

Thank you for your assistance.

[amaury1093]

In your case, as per the given link https://community.mimecast.com/docs/DOC-1369#451, the root cause is this:

It's definitely not NeedsRDNS. It's not really IpBlacklisted. I could create a 3rd category IpGreylisted.

[amaury1093]

The introduction of a new category, "IpGreylisted," emphasizes the dynamic nature of categorizations in real-world scenarios.

This prompts the realization that there may be additional categories beyond the existing ones like "IpBlacklisted" or "NeedsRDNS." It highlights the evolving landscape of email verification and the need for human intervention to discern and categorize unknown scenarios effectively.

In essence, the understanding is that we may not be certain of all potential categories generated when the "is_reachable" field is marked as "unknown," underscoring the importance of ongoing human involvement for accurate interpretation.

If there are further considerations or specific steps you recommend for community involvement in this process, I'd be eager to contribute.

Why are you pasting a ChatGPT response?

[ewhent]

I am just reframing my texts just so that I sound appropriate and correct

"So now this is a third category and there can be more than this right? so basically we arent sure of all the categories that can be generated when "is_reachable" field is "unknown" so it needs human intervention."

this is what I wanted to convey but just for making it sound correct I reframed it