Do system administrators have too much power?

Yesterday, Laura brought a thread from last week to my attention, and the old-school ISP admin and mail geek in me felt the need to jump up and say something in response to Paul’s comment. My text here is all my own, and is based upon personal experience as well as those of my friends. That said, I’m not speaking on their behalf, either. 🙂
I found Paul’s use of the word ‘SysAdmin’ to be a mighty wide (and — in my experience — probably incorrect) brush to be painting with, particularly when referring to operations at ISPs with any significant number of mailboxes. My fundamental opposition to use of the term comes down to this: It’s no longer 1998.
The sort of rogue (or perhaps ‘maverick’) behavior to which you refer absolutely used to be a thing, back when a clean 56k dial-up connection was the stuff of dreams and any ISP that had gone through the trouble to figure out how to get past the 64k user limit in the UNIX password file was considered both large and technically competent. Outside of a few edge cases, I don’t know many system administrators these days who are able to (whether by policy or by access controls) — much less want to — make such unilateral deliverability decisions.
While specialization may be for insects, it’s also inevitable whenever a system grows past a certain point. When I started in the field, there were entire ISPs that were one-man shows (at least on the technical side). This simply doesn’t scale. Eventually, you start breaking things up into departments, then into services, then teams assigned to services, then parts of services assigned to teams, and back up the other side of the mountain, until you end up with a whole department whose job it is to run one component of one service.
For instance, let’s take inbound (just inbound) email. It’s not uncommon for a large ISP to have several technical teams responsible for the processing of mail being sent to their users:

  • the aforementioned system administrators (who are responsible for running the operating system and base-level support applications — but not the hardware; that’s handled by the hardware team),
  • the application administrators (who manage the process(es) that handle the actual SMTP transactions),
  • and the database administrators (this volume of mail most likely not happening strictly using flat files.) (Oh, and the database hosts have separate hardware administrators and system administrators, too.)

You’ll note that none of these groups have taken responsibility for saying what actually gets to be delivered. In most cases, at most large ISPs, it’s simply not their job. Their jobs are simple: Keep their piece of the machine up and performing within acceptable technical parameters.
The decision to block (or unblock) messages (whether by IP, domain, content, or any other criterion) is made by an entirely different team, with a different set of marching orders. At many ISPs, these people don’t even report into the same organization as the guys listed above. These folks go by many names, but I’ll use the term ‘Postmaster’ here. Postmaster teams have a weird job that’s both science and art.
The science part is pretty easy, as it’s supported by data provided by users. For instance: how many complaints are we getting about a sender and what percentage of messages we receive from the sender results in complaints? (It’s important to remember that those are two very different things.) Since this part of the job is is so data-driven, it is often at least partially automated, or at least streamlined via tools. As dashboard displaying messages from suspected senders or those containing suspected content, with links to or copies of the supporting data would allow the Postmaster team to proactively review inbound messages that may not have yet triggered automated systems, but that are likely to in the near future. (Oh, and this dashboard was probably written by a tools team (still not the system administrators!) who have access to the hosts where the logs are kept (… need I even say it?))
The ‘art’ part is where things get tricky, and is one reason actual system administrators shy away (or run screaming) from this type of work. There are potential legal ramifications to this sort of thing, particularly when blocking on message content (as opposed to message source). What percentage of messages that generate complaints is acceptable? What if nobody (for whatever reason) ever complains, but the message contains illegal content? What happens if a small, but vocal, number of people complain? Do we have a partnership (it happens) with the sender that in any way changes our response to complaints about their messages? Do we attempt to work with the sender prior imposing a block, or simply block the incoming stream without warning? What is the best way to block this sender? Should we attempt to block similar messages? If so, how do we identify these messages?
These are all squishy, unquantifiable things, many of which can be (more or less) legally defined, but not necessarily implemented via a particularly elegant piece of code. Human intervention is required. Actual people actually looking at messages and complaints, taking them in context, comparing that context against the minimal guidelines provided by the various technical (host, system, database) admins, as well as the more nebulous legal and policy guidelines provided by any number of groups: sales, marketing, legal, etc. Calls (like, actual phone calls, not decisions) need to be made.
I have a number of years as a system administrator under my belt, most of them spent at large ISPs, and I speak from experience when I say I know of very very few people who sign up to be a system administrator who want anything to do with this kind of work.
(All of that was my long way of saying that any ISP with a significantly large number of users is long past the point where such unilateral decisions can be made. Or, if they can be made, systems are assuredly in place that they cannot be made without being noticed. Any single player who decides to block all mail from ‘Opposition Candidate’ had best be ready to have technical- and policy- based reasoning at the ready, because actions will need to be justified, and in short order.)

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A lot of people think content reputation is about specific words in the message. The traditional content explanation is that words like “Free” or too many exclamation points in the subject line are bad and will be filtered. But it’s not the words that are the issue it’s that the words are often found in spam. These days filters are a lot smarter than to just look at individual words, they look at the overall context of the message.
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Even when we’re talking content filters, the content is just a way to identify mail that might cause problems. Those problems are evaluated the same way IP reputation is measured: complaints, engagement, bad addresses. But there’s a lot more to content filtering than just the engagement piece. What else is part of content evaluation?

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URL reputation and shorteners

A bit of  a throwback post from Steve a few years ago. The problem has gotten a little better as some shortening companies are actually disabling spammed URLs, and blocking URLs with problematic content. I still don’t recommend using a public URL shortener in email messages, though.
Any time you put a URL in mail you send out, you’re sharing the reputation of everyone who uses URLs with that hostname. So if other people send unwanted email that has the same URL in it that can cause your mail to be blocked or sent to the bulk folder.
That has a bunch of implications. If you run an affiliate programme where your affiliates use your URLs then spam sent by your affiliates can cause your (clean, opt-in, transactional) email to be treated as spam. If you send a newsletter with advertisers URLs in it then bad behaviour by other senders with the same advertisers can cause your email to be spam foldered. And, as we discussed yesterday, if spammers use the same URL shortener you do, that can cause your mail to be marked as spam.
Even if the hostname you use for your URLs is unique to you, if it resolves to the same IP address as a URL that’s being used in spam, that can cause delivery problems for you.
What does this mean when it comes to using URL shorteners (such as bit.ly, tinyurl.com, etc.) in email you send out? That depends on why you’re using those URL shorteners.
The URLs in the text/html parts of my message are big and ugly
Unless the URL you’re using is, itself, part of your brand identity then you really don’t need to make the URL in the HTML part of the message visible at all. Instead of using ‘<a href=”long_ugly_url”> long_ugly_url </a>’ or ‘<a href=”shortened_url”> shortened_url </a>’ use ‘<a href=”long_ugly_url”> friendly phrase </a>’.
(Whatever you do, don’t use ‘<a href=”long_ugly_url”> different_url </a>’, though – that leads to you falling foul of phishing filters).
The URLs in the text/plain parts of my message are big and ugly
The best solution is to fix your web application so that the URLs are smaller and prettier. That will make you seem less dated and clunky both when you send email, and when your users copy and paste links to your site via email or IM or twitter or whatever. “Cool” or “friendly” URLs are great for a lot of reasons, and this is just one. Tim Berners-Lee has some good thoughts on this, and AListApart has two good articles on how to implement them.
If you can’t do that, then using your own, branded URL shortener is the next best thing. Your domain is part of your brand – you don’t want to hide it.
I want to use a catchy URL shortener to enhance my brand
That’s quite a good reason. But if you’re doing that, you’re probably planning to use your own domain for your URL shortener (Google uses goo.gl, Word to the Wise use wttw.me, etc). That will avoid many of the problems with using a generic URL shortener, whether you implement it yourself or use a third party service to run it.
I want to hide the destination URL from recipients and spam filters
Then you’re probably spamming. Stop doing that.
I want to be able to track clicks on the link, using bit.ly’s neat click track reporting
Bit.ly does have pretty slick reporting. But it’s very weak compared to even the most basic clickthrough reporting an ESP offers. An ESP can tell you not just how many clicks you got on a link, but also which recipients clicked and how many clicks there were for all the links in a particular email or email campaign, and how that correlates with “opens” (however you define that).
So bit.ly’s tracking is great if you’re doing ad-hoc posts to twitter, but if you’re sending bulk email you (or your ESP) can do so much better.
I want people to have a short URL to share on twitter
Almost all twitter clients will abbreviate a URL using some URL shortener automatically if it’s long. Unless you’re planning on using your own branded URL shortener, using someone else’s will just hide your brand. It’s all probably going to get rewritten as t.co/UgLy in the tweet itself anyway.
If your ESP offers their own URL shortener, integrating into their reporting system for URLs in email or on twitter that’s great – they’ll be policing users of that just the same as users of their email service, so you’re unlikely to be sharing it with bad spammers for long enough to matter.
All the cool kids are using bit.ly, so I need to to look cool
This one I can’t help with. You’ll need to decide whether bit.ly links really look cool to your recipient demographic (Spoiler: probably not) and, if so, whether it’s worth the delivery problems they risk causing.
And, remember, your domain is part of your brand. If you’re hiding your domain, you’re hiding your branding.
So… I really do need a URL shortener. Now what?
It’s cheap and easy to register a domain for just your own use as a URL shortener. Simply by having your own domain, you avoid most of the problems. You can run a URL shortener yourself – there are a bunch of freely available packages to do it, or it’s only a few hours work for a developer to create from scratch.
Or you can use a third-party provider to run it for you. (Using a third-party provider does mean that you’re sharing the same IP address as other URL shorteners – but everyone you’re sharing with are probably people like you, running a private URL shortener, so the risk is much, much smaller than using a freely available public URL shortener service.)
These are fairly simple fixes for a problem that’s here today, and is going to get worse in the future.

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Many mailservers, particularly those only serving a small number of users, are running spam filters in fire-and-forget mode, unmaintained, unmonitored, and seldom upgraded until the hardware they are running on dies and is replaced. Unless they do proper liveness detection on the blacklists they are using (and they basically never do) they will keep querying a list forever, unless it breaks something so spectacularly that the admin notices it.
So spread the word,

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