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Networking

Documenting a Network? 528

Philip writes "Three years ago I was appointed as a network manager to a barely functioning MS-based network. Since then I've managed to get it up and running — even thriving — but have been guilty of being too busy with the doing of it to document the changes and systems that were put in place. Now as I look back, I'm worried that I am the only one who will ever know how this network works. If I get hit by a bus or throw in the towel for any reason, I'd be leaving behind a network that requires some significant expertise to run. Ultimately, this won't be a good reference for me if they are trying to work out technical details for years to come. It looks like I'm going to have to document the network with all sorts of details that outside consultants could understand too (no, I don't want to be the outside consultant), especially since it's likely that my replacement will have less technical expertise (read 'cheaper'). Are there any good templates out there for documenting networks? Is anyone who has done it before willing to share some experiences? What did you wish your predecessor had written down about a network that you inherited?"
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Documenting a Network?

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  • I know... (Score:5, Funny)

    by EdIII ( 1114411 ) * on Tuesday May 26, 2009 @12:17AM (#28091439)

    What did you wish your predecessor had written down about a network that you inherited?

    The Passwords.

    • Re:I know... (Score:5, Insightful)

      by Drinking Bleach ( 975757 ) on Tuesday May 26, 2009 @12:33AM (#28091545)

      Whether the comment was intended to be funny, I find this to actually be a serious issue...

      • Re:I know... (Score:5, Insightful)

        by Acer500 ( 846698 ) on Tuesday May 26, 2009 @08:08AM (#28093801) Journal
        Something I found to be VERY good policy that was implemented at my former position (as Network Admin) was to hand to the boss (CEO, CIO or whatever) a sealed envelope with EVERY relevant password (most importantly the admin password :) ), to be held in the company's vaults (if your company has such a thing of course, or similar).

        Whenever an important password was changed, I would hand over the new envelope :)
    • Re:I know... (Score:5, Interesting)

      by 2Bits ( 167227 ) on Tuesday May 26, 2009 @12:37AM (#28091561)

      This may sound funny, but I recently had the same experience. I took over the position of CTO of an electronic payment company, and after one week, I figured a lot of critical systems are missing root password, including Linux, AIX, HP/UX and SCO Unixware. No one knows the password, it's been changing hands so many times, and the people who were responsible for those machines have left, without leaving the passwords behind.

      Those are critical systems that must run 24x7. We had to rebuild the system on new machines, re-route transactions to the new machines, and shutdown the old ones to recover (single user mode).

      And that's a platform handling over 400 billion in transaction per year. Scary. But that's the easiest problem I have inherited, mind you.

      • by Anonymous Coward on Tuesday May 26, 2009 @01:52AM (#28091895)

        So that's what happened during the bank collapse!

  • by TornCityVenz ( 1123185 ) on Tuesday May 26, 2009 @12:18AM (#28091447) Homepage Journal
    Use Post-its.
    • by FooAtWFU ( 699187 ) on Tuesday May 26, 2009 @12:24AM (#28091489) Homepage
      The nice thing about post-its is that they can be updated very easily when you're fiddling with the device. That doesn't work if you're configuring it remotely, though. :|

      The next step up from a Post-It, though, is a snazzy label-maker. My portion of the company uses these extensively to document our development lab (we do some NMSy stuff). Of course, it's not a production network, and standards are a little different.

  • Good News (Score:5, Interesting)

    by N3Roaster ( 888781 ) <nealw&acm,org> on Tuesday May 26, 2009 @12:22AM (#28091473) Homepage Journal

    Your successor will never find any documentation that you leave behind (or if you show it to them they won't bother with reading it) and by the time they notice it they'll have already screwed things up to the point where the documentation will be obsolete. This means you can save yourself the trouble of doing the documentation unless that documentation is going to make you more effective while you're there.

    • Re:Good News (Score:5, Insightful)

      by BrokenHalo ( 565198 ) on Tuesday May 26, 2009 @01:14AM (#28091715)
      ...or if you show it to them they won't bother with reading it

      This is more to the point. Most network admins have the attention span of a flea and won't read past the first sentence of anything you write; actually, I could probably expand that statement to include most people generally. Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
      • by MaskedSlacker ( 911878 ) on Tuesday May 26, 2009 @01:32AM (#28091785)

        You just thought I wouldn't catch a reference to Cicero's De Finibus Bonorum et Malorum.

        Original Lation from which it was derived: ...neque porro quisquam est, qui dolorem ipsum, quia dolor sit amet, consectetur, adipisci[ng] velit, sed quia non numquam eius modi tempora incidunt, ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit, qui in ea voluptate velit esse, quam nihil molestiae consequatur, vel illum, qui dolorem eum fugiat, quo voluptas nulla pariatur?
                At vero eos et accusamus et iusto odio dignissimos ducimus, qui blanditiis praesentium voluptatum deleniti atque corrupti, quos dolores et quas molestias excepturi sint, obcaecati cupiditate non provident, similique sunt in culpa, qui officia deserunt mollitia animi, id est laborum et dolorum fuga.

        English:

                Nor again is there anyone who loves or pursues or desires to obtain pain of itself, because it is pain, but because occasionally circumstances occur in which toil and pain can procure him some great pleasure. To take a trivial example, which of us ever undertakes laborious physical exercise, except to obtain some advantage from it? But who has any right to find fault with a man who chooses to enjoy a pleasure that has no annoying consequences, or one who avoids a pain that produces no resultant pleasure?
                On the other hand, we denounce with righteous indignation and dislike men who are so beguiled and demoralized by the charms of pleasure of the moment, so blinded by desire, that they cannot foresee the pain and trouble that are bound to ensue; and equal blame belongs to those who fail in their duty through weakness of will, which is the same as saying through shrinking from toil and pain.

        What was that about my attention span?

      • by Tiger4 ( 840741 ) on Tuesday May 26, 2009 @02:00AM (#28091933)

        ...fellatio uber alles...

        WTF???

  • get some help (Score:5, Insightful)

    by Jean-Luc Picard ( 1525351 ) on Tuesday May 26, 2009 @12:23AM (#28091481)
    Sounds like a very easy way to over work and over stress your self, get some help one way or another. Summer is coming and I'm sure there are plenty of Comp Sci/Network Engineer/IT students that could of help. It may not be a bad idea if you make a plan of some kind before you go head in.
    • by node159 ( 636992 )

      I concur, nothing like showing a fresh grad the realities of IT by making him document a network without assistance.

      On another note, if you ever expect some form of job mobility or flexibility, theres nothing like saying 'heres the documentation, cya'.

  • Documenting teamwork (Score:3, Interesting)

    by Anonymous Coward on Tuesday May 26, 2009 @12:24AM (#28091491)
    1. Simply begin documenting, its a work in progress..never finished. 2. Select a worthy staff member from your org, with the brain cells (and desire)to start learning networking, and begin to train him/her on what you are documenting. 2.a refrain from selecting the network thinks-he-knows-it-all type, instead pick anyone else with the skills listed in 2.
  • Alternatively... (Score:2, Interesting)

    by Anonymous Coward

    Professionalism be damned, we're in the middle of a recession and you're wanting to make yourself dispensable? Go ahead by all means, but pass your boss my number :)

  • What about? (Score:5, Informative)

    by DaMattster ( 977781 ) on Tuesday May 26, 2009 @12:27AM (#28091507)
    A good tool like dia which can allow you to create a network diagram. When it comes to documenting a network, a picture can be worth a thousand words. Or you could also use MS Visio as it is, perish the thought, a good tool. A good, detailed diagram can come in very handy as a reference tool for your own use in case of a failure.
  • schematics (Score:5, Informative)

    by ClaytonianG ( 512706 ) on Tuesday May 26, 2009 @12:28AM (#28091513)

    Basic network documentation:

    I've found that starting out with the very basic physical layout and working your way up in complexity is greatly beneficial.

    i.e. start out documenting network cable runs including cable type. follow it by switch layout. follow that by routers and vlan setups. follow that by the servers that provide basic network functionality(e.g. DHCP, etc...). If this is a windows network, that would likely mean detailing the domain controller setups. From their systematically document the systems in order of importance to the business, etc...

    Also, visual diagrams are extremely helpful.

  • Let's be real (Score:5, Interesting)

    by mcrbids ( 148650 ) on Tuesday May 26, 2009 @12:28AM (#28091515) Journal

    Short answer: don't worry about it too much. Put together enough that it looks like you've done something then go have a beer.

    You could have the most amazing docs the world has ever known - with passwords and clear instructions - ad the odds are about 20% that the next guy will even read them.

    The next guy will figure that he/she knows much more than you as evidenced by the fact that they are there and you are not. And, the cheaper they are (read: inexperienced) the more likely this is to be the case. When things go wrong, they will blame you anyway.

    So document away, but for YOUR sake so that if/when you are called in after the new guy horkens everything, you can have an easy time putting it all back together. But don't wait for the call... people will put up with almost anything when pride is on the line.

    And go have a beer.

    • by jotaeleemeese ( 303437 ) on Tuesday May 26, 2009 @01:54AM (#28091899) Homepage Journal

      No wonder our field and many of our professions have such a bad reputation.

      I have read only a few posts and two (moded up 5) say pretty much to ignore the issue.

      In several networks I have worked with fundamental information was non existent. This translated in lost time, down time and actually losing money (if you lost your job in one of those companies recently, the indolent SAs or Network administrators may be partly to blame).

      You never know who the next guy will be, if he is less experienced or capable then the documentation will be very valuable, if he is more experienced or capable then you would have saved their time to do some real work, after all they (and you) have not being hired to do forensics.

      How a professional can hide behind the "let's be real" nonsense is beyond the pale.

  • by bjcopeland ( 70793 ) on Tuesday May 26, 2009 @12:29AM (#28091517)

    For me, visio's are great and everything, passwords too, but really the most valuable thing you can do is document single points of failure, outdated software/hardware, etc., license keys/expiration dates, cert expiration dates, personal support contacts you have and all vendor relationship details as well are essential. Do you use change control? If you do, go back and comment your changes, if not, do the best you can at explaining why things are the way they are. Get some open source software that is good at indexing data and create a searchable knowledge base from the information above. Don't concentrate on docs that can be found on the web at first because any admin worth their salt will know where to look for how to's, etc. Focus on the why's, the where's and disaster recovery.

    My two cents...

  • by Anonymous Coward on Tuesday May 26, 2009 @12:30AM (#28091525)

    1. Viseo overview of the network drawing with complex areas drawn out specific detailed viseo's (even a scanned sketch or paint drawing is better than nothing)
    2. A spreadsheet with circuit ID's mapped to router and interfaces.
    3. Document the trunk interfaces as well as the LAG's (Link Agrregation Groups, port channels, whatever you want to call it)
    4. TACACS passwords / domain logins in a secure location (or radius or diameter or whatever you use)
    5. Data center capacity as a function of 1. Rack Space, Cooling Capacity, Electrical Load.
    6. Write brief knowledge articles describing any problem areas and explaining a history of anything you think would be hard to figure out easily. No need to go hog wild, just re-brand the RCA documentation you have. You do have Root Cause Analysis right?
    7. Network protocol hierarchy map. Where are your major redistribution points, what is your routing strategy etc.
    8. If you have a voice network document all your DID's, PRI trunks, Gatekeepers, Dial Plan, and any translations you use on h.323 gateways or how MGCP or SIP is configured. If you have a complex call center you should probably pay to have it professionally documented in down to the minute detail.
    9. SSID's and BSSID's for any wireless you may have as well as passwords, 802.1x authentication methods, along with linking documentation.
    10. Make the documentation part of your CMR process (Change Management Review) and incorporate it into the time allotted for a change.

    I know these are just rough ideas and you should get many more ideas from all the smarter people on here than myself, but whatever advice you get I would say you would need to have the documentation update able via subversion, or some document control system and have some kind of review process for it, even if it means getting together over pizza with some of the other groups and asking them about their environment and getting pointers and possibly help on documenting it all. Documentation is a full time effort and IMHO there is no such thing as too much documentation. You would be surprised how good documentation can aid you in problem resolution down the road or aid vendor support in helping you resolve a major outage. The three basic principles of network care are document document document. :)

    Cheers,

    Anonymous Coward.

    • Re: (Score:3, Insightful)

      by Spyder ( 15137 )

      The AC has a very good list, I'll see if I can add anything to it.

      Network diagrams should be at a network, physical and datalink layers. Only the simplest networks can have all this information on a single diagram and have it be useful. Seperate the network drawing from the datalink and physical drawings as requred but be sure to leave enough detail to connect the drawings (Visio has a nice linking feature for this). Also keep a spreadsheet or database of assigned networks, IP ranges, and assigned static

  • TiddlyWiki (Score:5, Informative)

    by bradley13 ( 1118935 ) on Tuesday May 26, 2009 @12:31AM (#28091533) Homepage

    On the side, I manage a small network, and I've also wondered the same sort of thing: if someone else needed to find their way around, where would they start.

    A Wiki makes for a really nice way to document things, not least because you can include all sorts of cross references. For example, a list of servers, with links to the services they provide - and a list of services, with links to the servers. But Wiki's normally run on servers, which leaves your successor with a chicken-and-egg problem.

    A bit of random surfing turned up TiddlyWiki [tiddlywiki.com], which is a Wiki in a single HTML file. A really elegant bit of engineering, and very handy for self-contained documentation. Since the entire Wiki is just a single file, it's easy to protect. I wound up with two: one with "public" information describing the general architecture and one with private information (including passwords). The private one you can put on a USB-stick in a safe, hand to your boss, or whatever seems appropriate...

  • setup a wiki (Score:5, Interesting)

    by blkwolf ( 18520 ) on Tuesday May 26, 2009 @12:33AM (#28091539) Homepage

    At my last few companies and my current one that I work out, one of the first things I do is setup an internal only Wiki server.

    Not only does this let me document everything I can about the network but I also try an train my co-workers in using it to document information they feel is important for their job too.

    The effectiveness though seems to be related to the level of computer literacy of the user, i.e. my last company the software developers went crazy with it and documented everything they could think of. But other than them or us in the I.T. dept, no one use would hardly touch it at all.

    Either way it's still a simple method for your to store notes, diagrams or any information about your network in an easy to find single location that you feel would be important to the company should you leave for any reason.

  • by Anonymous Coward on Tuesday May 26, 2009 @12:39AM (#28091565)

    Why not use an automated too?

    www.open-audit.org

  • Unlike software documentation, in a network there is more than one approach, pretty much a function of the amount of people that have to fiddle with the network at any given time. Usually there is physical laying of cables (where are they), box location and naming (labeling and Visio-sheets), peripherals (printers, faxes, phone system), box setup (OS and processes), server process configuration specifics and client requirements. And then there's that (what I think) very important document that describes w

  • Am I the only one who first thought, "If you have done the network correctly, it should explain itself"? Overly-complex networks take overly-complex documentation and overly-complex people to run and maintain. Mind you, there's a difference between correctly-complex and incorrectly-complex, but at the same time, every level of difficulty you go upwards in the configuration scale you exponentially increase the need for carefully calculated and layed-out systems. Ok, ok...now that I'm thrust back into rea
  • Contact Numbers (Score:5, Insightful)

    by DragonDru ( 984185 ) on Tuesday May 26, 2009 @12:46AM (#28091603)
    The phone numbers/emails for points of contact in other departments/companies.
    You likely don't run *everything* and the new person needs to know who to contact when the interaction between inside and outside fails.
  • by carlocius ( 153486 ) on Tuesday May 26, 2009 @01:02AM (#28091665) Homepage

    My job requires me to do exactly what you're looking to do but for multiple companies/networks. Then, as soon as I'm done, I usually pack up and go or get hired in and fix the network.

    Since I'm writing the Network Overview for managers AND potential future network managers I tend to write mine in the following format:

    1) Synopsis of what the network does for the company, what general technologies they use (Windows AD vs *nix OD, thin clients vs Windows boxes, Cisco vs Brand X), and what the LOB software is.

    2) Points of contact for the ISP and other providers (anti-spam, anti-virus, hardware, etc). Passwords for various accounts and services.

    3) Logical network overview map (visio), containing firewalls, routers, switches, other devices, open/forwarded ports, IPs, what the servers do, what vlans are in place, Quick explainations for why (such as why vlan vs a seperate subnet).

    4) Physical map of devices if the complexity of the network calls for it.

    5) Software notes, what apps are critical for the business and which systems they rely on.

    Then, for my specific job I have to do the following:

    6) Licensing issues.

    7) Network weaknesses/points of failure.

    9) Other rec's.

  • by XDirtypunkX ( 1290358 ) on Tuesday May 26, 2009 @01:05AM (#28091673)

    Draw a horrible diagram in Visio (or similar) of what's connected where without any indication how it actually works!

  • If the network itself (switches and routers) is built on Cisco, there are commercial (SolarWinds) and Freeware (NeDi [www.nedi.ch]) tools to document the interconnections, VLANs, and configs. Assuming you've left CDP enabled and standardized your SNMP community strings, NeDi does a fine job of documenting a network with minimal effort. I've found switches the network team didn't even realize existed just from using the NeDi discovery mode and adding 'public' to the list of SNMP strings to try.
  • Easy (Score:2, Funny)

    by Viree ( 214760 )
    nmap -sS -O 10.0.0.0/8 > handover.txt
  • by onyxruby ( 118189 ) <onyxruby@ c o m c a s t . net> on Tuesday May 26, 2009 @01:23AM (#28091739)

    Present client I am at I inherited a network of about 15,000 clients that was previously managed my a very incompetent IT department. Started by looking at the existing flowcharts and discovered that almost everything that was documented was wrong... Long story short I have been spending a fair bit of time reverse engineering their production environment so that we could accurately document it. Unfortunately we had come to the conclusion that we can use /nothing/ that the previous administrators left behind for documentation. You don't want someone like me coming in and looking at your documentation and declaring you incompetent, it can cost you your job.

    You haven't detailed the size of your organization to know if you will need sign off from other departments or not. If possible try to get sign off so that they have a reference and you can create a standard that can be used to fix things and to ensure your designs don't get trampled by a new admin in another department. You really need to provide more detail on your environment for people to answer you.

    I do most work in Visio, starting at 50,000 feet and working my way down. At this level I need to document network topology, server distribution and database server distribution. I work my way down from there using a zoom in style that has served me well for 30 some clients. Depending on the size, complexity and your area of responsibility you may need to flowchart anywhere from a 2-3 levels to potentially dozens of disparate processes. You haven't mentioned much about process development, I assume you want people to know how to do at least critical portions. Never write a process without flowcharting it, this will save you grief by getting people to focus on the process instead of a step by step set of directions. It takes someone fairly good to document the complex and make it look simple, that is your job at this point in time.

    The bottom line is that your documentation should show dataflow for each critical system. As long as you can do this someone else can step in and work with what you have, even if they may not understand a given piece. One of the big advantages of flowcharting everything (especially processes!) is that this will readily show you weakness and holes that may have been previously overlooked. When flowcharting complex processes don't be afraid to have a single point represent an entire additional complex process that can be distictly referenced of it's own accord (as an car repair manual of mine once described the process to replace a crankshaft "Step 1. Remove Engine".) If you try to put to much detail in a given process you lose your audience and the value of the documentation.

    Bottom line when I am done with a design document it covers server, network, database and client topology in varying levels of detail with dataflow. A typical design document I would turn over would be 150 pages with most of that broken down into different sections describing what was done, why it was done, the best practices followed for build, and best practices for lifecycle. The document typically does not get read by any one person, instead it would be a reference for a number of different departments that will each reference it according to their own needs.

    • Re: (Score:3, Insightful)

      by malkavian ( 9512 )
      Ok, I think that establishes you as a system auditor, rather than an administrator. Without having seen the documentation you produce, I'm not going to judge either way (I've seem some 150 page documents that are invaluable as a crib sheet for some systems, and I've seen way too many 150 page documents that aren't worth the paper they were printed on).
      From the sound of the original poster, he's in a tough spot. Way too much to do, and not enough time to do it (sole network admin).
      I think this Dilbert ca [dilbert.com]
      • Re: (Score:3, Insightful)

        by onyxruby ( 118189 )

        You are both on and off the mark. First, I'm an enterprise architecture consultant for a living, I've done lifecycle administration in the past and do some now. I've certainly done audits, even to the point of being brought overseas, but that was only about 20% of my work. Once the audit is done my job was typically to follow up with how to bring things up to par. Staffing, architecture, servers, licensing and bandwidth considerations all come into play and receive my recommendations. I am far more likely t

        • Re: (Score:3, Interesting)

          by Falconhell ( 1289630 )

          I find the more long words in someones job title, the less useful the function they actually perform.
          Good title you have there.

  • by isj ( 453011 ) on Tuesday May 26, 2009 @01:43AM (#28091837) Homepage

    If you are in the server room, and you have:
    A: a spreadsheet that your predecessor made.
    B: a post-it note on the switch saying it what it does.
    Which one do you trust?

    For the physical/low-level network the documentation should be in the network. Just like source code should contain comments about this particular piece of code, a similar approach works reasonably for the physical network. I see no point in a having an outdated spreadsheet. It is more useful that the cables and ports are labelled and numbered, that there is a post-it note on a switch say where the links go, etc.
    The grand overview should be in electronic form, though. A scanned hand drawing is fine. A photo of a whiteboard drawing is fine too.

    For the logical network put comments whereever possible. On settings, VLAN configurations, server connections, account setups, ...
    Again, the grand overview should be in electronic form.

    I have found it useful that the information is timestamped, so you know when it was last valid.

  • by Pathway ( 2111 ) <pathway@google.com> on Tuesday May 26, 2009 @02:04AM (#28091947)

    Ah, you're not following the MACK(TM) Truck Rule.

    The MACK Truck Rule (MTR for short) is a measuring stick which we use do determine if a solution is good for us. Basically, it's an objective measurement of the level of expertiese required to do something. Basically, the MTR has you ask yourself (Or your team) the following question:

    If the person(s) responsible for a task was suddenly hit by a MACK(TM) truck, How much time would it take for somebody else, untrained, to complete that task if needed?

    If that amount of time is unreasonable*, It doesn't follow the MTR. Notice the caveat for unreasonable; this is the subjective part. What' unreasonable for one may be reasonable for another. This needs to be decided for yourselves.

    Documentation always helps difficult tasks pass the MTR. So can good support. I try to leave a readme in the place where the installer is for a difficult program. I'm now begining to use FreeMind to map out networks and servers. I have a good ticket system for all our repairs. Hopefully these things will make things easier the day I want to take a vacation.

    --Pathway

    • Re: (Score:3, Interesting)

      by Glonoinha ( 587375 )

      We used to have a similar 'BUS' rule (ie, what if so-and-so got hit by a bus) until someone we all knew got hit by a bus. That sucked, he was a good guy and we had just referenced that joke a week earlier.
      Now we have the 'LOTTO' rule (ie, what if so-and-so hit the lottery and left the company to be independently wealthy.)
      We all miss Dave. And most of us secretly wish he had documented his fucking code before getting hit by that bus.

  • Wiki Wiki Wiki (Score:5, Informative)

    by EEBaum ( 520514 ) on Tuesday May 26, 2009 @02:09AM (#28091979) Homepage
    I have a wiki set up for the company I admin. Each server on the network has its own page, with a standard set of categories...
    • Purpose
    • Access (IP addresses, names, special ports)
    • Services provided (and descriptions of the services)
    • Maintenance (to do at intervals)
    • Quirks (stuff that tends to go wrong and what I've done about it)
    • Installation Notes (anything special I did when installing the server or any software on it)
    • Captain's Log (an entry for each incident involving this server, what its symptoms were, what I did to fix it, etc.)

    I have a nicely formatted template page with all those categories set out. I also maintain a page of IP address assignments and an inventory of harware specs of all the machines in the office (which is helpful in the cases of "We need to reproduce a bug that only happens on ____ processor with ____ video card" and of "We're getting new machines. Who is in most dire need of an upgrade?").

    I write down everything in these, and find myself referring to them very often. My predecessor gave me a Word document with all his notes in it, which has been very useful, and I used that as a starting point for my pages. The wiki has saved me a ton of time, kept me organized, and serves as a great reference for me and for the inevitable next admin.

    The only caveat is if the wiki (or the server it's on) goes down. This has happened once, and my instructions for fixing the wiki were... on the wiki, so extra troubleshooting for me. Thus, I find it good practice to maintain a hard copy of the wiki pages, especially the page that tells how to fix the wiki.

    I'm running this on Redmine, which has proven to be bleedingly simple to use and administer, and much easier than trac, which we used before. It's especially nice having it on the intranet, as I'll just have a browser open to the wiki as I work on systems and refer to and update it as appropriate. It's very handy to document exactly how I performed a strange or experimental installation of some software that I'll want to replicate later without making myself crazy, and I'll take the extra few seconds to retype the commands I just used into the wiki from anywhere in the building, though I probably wouldn't do the same into a Word doc.

    It's not so much the mundane day-to-day that I find that important to document. It's the weird fixes, the trouble spots, the command line parameters, the installation procedures, the changes that shouldn't have fixed it but did, and the horrific chain reaction situations that make one piece of software crash because a seemingly unrelated piece of software has the wrong version of the 64-bit library. Things that take 4 hours to figure out and 3 seconds to implement... those are the ones to document, and those are the ones that I'd be kicking myself 20 months later for neglecting to write down. In an afternoon, any schmuck could walk into the building and figure out which network cable goes where. Documenting the strange bits (and the frustrations), though, can get a malfunctioning mail server back up and running in 3 minutes instead of 3 hours (which, of course, is secondary to good administration keeping the server from going down in the first place).

  • The overlooked parts (Score:4, Interesting)

    by Opportunist ( 166417 ) on Tuesday May 26, 2009 @02:33AM (#28092121)

    There are a few things that are often overlooked and outright forgotten when documenting networks. I had to take over a few networks, let's see what I usually miss:

    Every admin remembers to hand over passwords. Except for the routers.
    Routers and other "managed black boxes" are notoriously being left out from the list of passwords. Fortunately, more often than not it's the standard password because "nobody has to touch them but me anyway" (ignoring that, if people only touched what they should, passwords would be moot...)

    Every admin remembers to draw you a network layout. They don't tell you WHERE those switches physically are, though.
    In large companies (read: Lots of room to cover, independent of the number of people working there), this can indeed be a problem. Especially when there's not one single server room where everything is collected, when you have switches and routers hidden in cupboards and other "innocent looking" furniture, cables that appear out of nowhere and disappear into walls, without an indicator where they surface again. Or what purpose they serve, first of all.

    What HAS to be documented is the reuse of resources
    That's the worst of the "undocumented changes". When you find a switch that shouldn't be there, you know you have to investigate, you know something wasn't documented. When you find a certain box sitting where it is supposed to be, you don't investigate. You expect it to do what it allegedly does. If it does not and has been "recycled" to fulfill another role, the whole documentation goes out the window. Because now you start questioning EVERY piece of hardware.

  • Size? (Score:3, Insightful)

    by SpaghettiPattern ( 609814 ) on Tuesday May 26, 2009 @02:54AM (#28092225)
    Which size if the outfit you work for?

    If it is large enough (which it doesn't seem to be) you should divide stuff up in modules. Start from OSI layer 1 and work your way up.
    • Per site, draw down the physical segments of your network (LANs, PTP connections, routers, bridges, switches, modems, etc...)
    • If you manage MAC addresses -in which case I pity you- throw these in your inventory database, spreadsheet, backside of used envelope, etc...
    • Relate your IP networks to the physical segments you drew up before
    • Draw in the non IP-based protocols (NetBEUI/NetBIOS, IPX, SNA) and have them make sense in some kind of table.
    • Document vital routing/bridging protocols like OSPF, BGP, SNA, SRB
    • Document vital networking services like DNS, DHCP, BOOTP.
    • Document vital directory services like ADS, NDS, YP, LDAP-based.
    • Take care about email (as this typically will combine DNS and directory service.)
    • Let OS installations be done by sysadmins. Limit yourself to recommendations.

    If it's small, you probably wind up merging loads of stuff into one document in which a serious amounts of stuff is considered to be "the network" although it isn't.

    Having said this, there are places to go other than /. to get this information. You're not the first person that has to do this. Must be a slow day here.

  • by yelirekim ( 1371387 ) on Tuesday May 26, 2009 @03:15AM (#28092299) Homepage
    1. portscan everything on your entire network and spit it out into a text file
    2. set up a wiki
    3. paste the results of the portscan into the wiki
    4. start writing about everything that showed up


    i've actually done this before with a pretty high degree of success, pm me if you want some help setting it up
  • by Mista2 ( 1093071 ) on Tuesday May 26, 2009 @05:11AM (#28092771)

    My favourite technique for making sure documentation is done and updated, get the new guy to do it. Then he/she has to go all around the campus, locating servers and getting serial numbers form all sorts of odd equipment and making sure all of the support aggreements are current and the contact details for the vendors are accurate.
    The other favourite is if I find new equpment that has been installed and is not labelled or documented, I get the installer responsible to audit all similar equipment to make sure there are no other ones missed out. After haivng to crawl around dozens of risers and labelling or confirming all switches etc are correct and documented, they don't often make the same mistake twice.
    We also have a password management system which also allows details like how to install the management console or the URL to access a system for management to be stored.
    My answer to any question about "What is the password for X", or "what the hell is the name of the server for X applicaiton" is "Its in the store" Then if it isn't, we add it 8) Only takes a few times for the newbies to start looking up the information themselves first.

    The other key file is a massive Visio document with a summary page with a managment style overview, and then a document with everyhting in it in layers like an electircal diagram or building plan.
    Lay in the workstaitons VLAN, the switch management VLAN, the Servers VLAN, link to things that are self contained like all of the Firewalls and DMZ configurations.
    etc.

  • by jimicus ( 737525 ) on Tuesday May 26, 2009 @05:12AM (#28092783)

    First: You must make everything as self-documenting as possible. Label every server, every cable, every power lead to within an inch of its life. And establish processes which say "when a cable is moved or added, labelling is updated accordingly". If you don't have a labelling machine, buy one.

    That deals with basic "what's plugged in where" and is far more likely to stay up to date than a spreadsheet or wiki page.

    Second: Whatever you choose, it must be something which can scale to your needs and which you can live with.

    It will need regular updating - and quite frankly, very few people are able or willing to regularly update a single 200 page Word document complete with embedded spreadsheets, diagrams and photographs. A wiki - or even Sharepoint, if that's your thing - may be better. But if you do take the Wiki route, make sure you keep hard copies of the documentation which says "If the sh1t hits the fan, this is what you need to do to recover".

    Others have said "don't bother, your successor won't read it" - I say balls. Documenting is more than just helping your successor - it also helps you remember what is set up, clarify how things work and as part of the process you start to look at things and think "hang on a minute.... this document I've written describes something quite absurd. Are we really doing that?"

    Whether or not your successor reads it is really not your problem.

  • by Gyorg_Lavode ( 520114 ) on Tuesday May 26, 2009 @01:25PM (#28098379)
    If you're a masochist, you can always try and follow the DoD Architecture Framework [wikipedia.org] which defines multiple views of architectures (including networks). Once finished, there shouldn't be any question of what your network is, what it does, and how it does it, but you'd probably need an army of peons to put it together.

Never test for an error condition you don't know how to handle. -- Steinbach

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