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Comments: 149 +- Ask Slashdot: Directory Service Implementation From Scratch? on Thursday June 04 2009, @02:22PM
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An anonymous reader writes "I work at a small but growing startup company. Currently, our directory and authentication information is scattered across many systems and wikis, and is becoming increasingly difficult to manage. We are looking at centralizing this information in a directory service to minimize administrative overhead as we continue to grow. The service must support basic directory searches, as well as user authentication for Linux and Windows hosts. Although we are primarily a Linux shop, there are a handful of Windows systems that will be on a Windows Active Directory domain. Most directory servers seem to support integration with other directory servers, however it seems like it may be easiest to just use Active Directory for everything. Are there any pitfalls with this approach? If you had the chance to redesign your enterprise directory service without regard for legacy services, how would you do it?"
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Submission: Directory service implementation from scratch by Anonymous Coward
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Easy (Score:3, Informative)
Use AD.
Even though folks will fuss and whine about AD being not pure LDAP, for all intents and purposes it is, and we've got lots of Linux and other *nix boxes using it for authentication. And remember, you can always extend AD for your custom applications easy enough. It's simple enough that MCSEs can run it.
Re:Easy (Score:4, Informative)
This. AD's management tools are brutally efficient and understandable. The newest versions of Samba+KB5 make it trivial to authenticate *nix systems against it and have fully integrated, cross-platform user & privilege management with consistent uid's/gid's across all hosts. Assuming you throw the right amount of resources at it (at least 2 AD servers per tree in the forest, per site), and take advantage of the DDNS services, you'll have a really scalable, easily managed infrastructure for years to come.
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Re:Easy (Score:4, Informative)
It's hard to argue against AD - even in your situation where the Microsoft boxes comprise the minority of systems.
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While Unix boxes can authenticate to an Active Directory domain through the use of Samba and derivatives, the advantage of these services is that they can extend the LDAP schema with NIS attributes to provide native NIS authentication, and also, extend SMB sharing with NFS support to provide native
Win2k3 R2 (Score:2, Interesting)
Windows 2003 R2 has (virutally) the same IDMU as Win 2008.
I have implemented such a mixed environment, with one problem. As I pointed more and more liunx boxes at the AD running IDMU, the number of internal connections from the AD server to it's own LDAP port increased until they were all tied up. It got so the AD server could not even read its own global policies.
I had to implement a Linux NIS slave and point all of my Linux boxes at it instead of the AD server.
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I'd just like to point out that while you CAN use NIS with SFU and the like, unless its an old machine without Kerberos support and without NSS support, you really would want to use kerberos and nss_ldap to connect to an AD server with SFU installed. If you have old machines, sure, shoe horn them in with NIS, thats what its there for, but you should avoid it if possible, NIS is horribly insecure. The plus side of using kerberos is that no syncronization is required, AD will sync its kerberos server passwo
Re:Easy (Score:5, Insightful)
Use AD.
Even though folks will fuss and whine about AD being not pure LDAP...
You're not a developer, are you? Whether or not AD is a dream to work with depends heavily on what your job description is. If you are simply an administrator plugging random Windows or even Linux and *nix boxes into AD you might find it comparatively easy. If on the other hand you expect to have to develop custom applications of your own on non-Microsoft platforms that authenticate against AD or convert existing ones to use AD then it can be a painful experience to use AD. It's not an unsolvable problem mind you, just a really annoying one.
... It's simple enough that MCSEs can run it.
So is RHDS / Fedora Directory Server. I knew exactly nothing about LDAP or directory servers when I got my first directory server related project years ago. I still I got the thing set up and running inside of a couple of hours. Even an MCSE should be able to manage setting it up, hardening it and administrating it in a very short period of time.
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You can LDAP query AD like my moped can race in the Indy 500.
Re:Easy (Score:4, Interesting)
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Microsoft Hostility (Score:3, Insightful)
Uh huh. So what's wrong with AD?
Microsoft seems to design their protocols to be as hostile as possible to 'other' OSs (without being openly anti-competitive). This is good for their business plan but bad for users. A side effect of this is (like another comment in this thread noted), that it's really difficult to expand the system beyond what Microsoft wants you to be able to do.
Given that you're using mostly 'other' operating systems, I think it would be a big mistake to make the bulk of your systems beholden to a hostile mistress.
Re: (Score:3, Interesting)
The other thing you can consider is whether to split the directory services and the authentication.
At my last job we did the following:
- Use Windows AD for all windows machines
- Use NIS for passwd, group, automounter maps... everything but authentication.
- And then key the Linux machines to use Kerberos off the Active Directory
Now if I was doing it again, I'd do the following:
- Use Windows AD for all windows machines
- Setup up a UNIX/Linux based Kerberos domain that "trusted" by the AD Kerberos
- Use NIS, NI
NOT AD because of hidden complexity. (Score:2)
Re:Easy (Score:4, Insightful)
To someone equally fluent in both OS and MS systems, sure, an open source solution is fine, probably even superior. But the business case for using MS software is undeniable.
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Just go with AD (Score:4, Informative)
I really hate to say it, but I think Active Directory is most definitely the way to go. No other directory systems allows for as simple administration of a large number of windows computers, your windows clients will "Just Work" with it, and it isn't difficult to make windows boxes, wikis, etc authenticate against it (I've had to do this many times...).
Active directory lets you access it via LDAP which a lot of software packages understand (a note here, structure the LDAP binds such that the username is in the form of SAMACCOUNTNAME@WINDOWSDOMAINFQDN, this has worked almost every time for me).
The free version of Likewise Open will make it very easy for the linux boxes themselves to authenticate against AD without having to mess with any pam conf yourself, and if you pay them money you can even deploy GP's to linux boxes (disclaimer, I've never tried this part).
In sum, while I hate to say it, you can make almost any client solution work with AD either directly or via LDAP or Kerberos, and it's the best possible solution for windows client management, so I'd go with that.
Just my .02
Re:Just go with AD (Score:5, Insightful)
I've looked into LDAP/Kerberos authentication for my home LAN several times, and basically given up every time. There appears to be a software mix that will do the job, but each piece needs to be configured *just so* in order to work with all of the others. Furthermore, there appear to be a few people out there who really know their stuff, and to them I'll bet this is all easy.
But it appears that those people all work for companies that sell Directory Server services. They're quite willing to be helpful on specific questions, but the overall integration is still not well documented, from what I can see. As near as I can tell, it's like the Bad Old Unix days, when everyone wanted to be The Solution - for a price. I haven't really looked at the RedHat Directory server or similar products, wishing to use the pieces, and wishing for integration documentation.
Why this on a home LAN? For some odd reason, I've tried to run my LAN on industrial-strength software - BIND, ISC DHCP, etc. I'm used to single-sign-in at work, and would really like it at home, given that $HOME is shared over NFSv4. I also usually am too busy doing other things, which is another reason why there's been no progress in years.
Maybe an integrated OSS Directory Server will make it into my house, but there's no way I'm footing the bill it would take to add AD, here.
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Twilight Zone? (Score:5, Funny)
Wow.. did I wake up in another dimension? Are slashdotters actually recommending MS products today??
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AD and OpenLDAP are like first cousins.
big difference is Open LDAP you have to create your schema. with AD Microsoft did the work for you and upgrading is easy. if you first deployed AD with Windows 2000, upgrading to later versions of windows and AD apps is easy. MS ships ldif files with any of their apps that extend AD with new classes and objects that do this automatically. saves you a lot of time.
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Re:Twilight Zone? (Score:4, Insightful)
Wow.. did I wake up in another dimension? Are slashdotters actually recommending MS products today??
But of course - did you not realize that the majority of slashdot readers are microsoft windows users?
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Ohhhh Barnacles! It's Backwards Day!
Re:Twilight Zone? (Score:5, Insightful)
Not really, you can make OpenLDAP have the required schema for windows.
Of course, then you need to add a kerberos server since OpenLDAP doesn't do that.
Then you need to add Samba so you can get the RPC calls that go along with Windows Clients.
Its not that it can't be done, its that its just FAR easier and more reliable to just pay the money for Windows.
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MS is pretty clear, any connection to a Windows server requires a CAL, period.
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Let me restate. Any client that makes a connection to a Windows server requires a CAL to access the server. Its not per connection in most cases (is in some though!), but if you're connecting to a Windows server, you need a CAL to account for it somewhere.
Windows server web edition has some allowances to keep the CAL count lower, but since it doesn't run AD its not part of the discussion here.
Brokenware (Score:2)
It's just another dimension of Microsoft's brokenware mentality. They design a product, then they break it before selling it to you so they can sell you an upgrade to a working version. CALs are the server equivalent to the PC/workstation scenario. They don't provide different versions of Windows with different capabilities. They do provide different versions of windows intentionally broken to different degrees. They're creating an artificial feature set that they can up-sell later.
It's diabolical, rea
Re: (Score:3, Informative)
The licensing for Windows Server doesn't necessarily have anything to do with the size of the directory.
With Server 2008, you have a matrix of options. You can choose whether you want to count licenses by computers or users by the type of CAL you buy (Device or User). Then, you can choose whether you want to license the number of simultaneous connections to a single server (per-server) or by the number of discrete users or devices that have accessed any server (per-user or per-device). Clearly, if you only
Novell.......no seriously (Score:4, Insightful)
Re: (Score:3, Informative)
+1 On Novell's IDM, it is *hands downs* the best Directory Services product out there.
Though if you don't want to spend the bucks for it (it's worth it, seriously), I would recommend just using AD.
As others have said, AD just sort of works, and everything can interact with it.
I'd personally recommend it over SAMBA/OpenLDAP, as I've beat my head against the wall one too many times trying to use SAMBA/OpenLDAP as a Windows Domain. It's just not worth the time or frustration.
Re: (Score:3, Interesting)
and +1 for eDir from me as well.
I have a blackbelt in directory management (AD, eDir and OpenLDAP)
eDirectory has a nasty habit of being virtually unkillable and is by far and away the most flexible. With 8.8 you can run multiple trees on a host (in MS speak think of multiple domains on a single DC) No waste of a system to just do DC duties for one bit of your system.
If you want the most powerfull directory option then use eDir as your metadirectory and then use IDM to populate other directories and applic
My choices (Score:4, Informative)
2.) Active Directory
3.) OpenLDAP
4.) Novell eDirectory (personally my least favorite)
I would probably jump for RHDS first, then AD. The only problem with OpenLDAP might be getting a similar level of support to the first two. Support is exactly why I would never choose eDirectory. I have (personally) had abysmal experiences dealing with Novell. Others may disagree though. And of course there probably are other options.
Re: (Score:3, Insightful)
would it not be possible to configure a single server, that proxies or delegates queries to all the other servers he has set up.
I asked about proxying openLDAP to AD, so I could have users in both, yet query them all just by asking the openLDAP server. If this was possible for multiple delegated servers, then this is the approach I'd take - start with 1+all the old ones, then gradually migrate them into just a few servers.
and yes, I'd probably go for RHDS, Active Directory seems to be one of those products
Re: (Score:2, Informative)
SunDS, FDS and Novell eDirectory are all based on Netscapes DS,
FDS and RHDS are the direct descendants of Netscape DS, which was purchased by AOL and then by Redhat who then Open Sourced it.
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SunDS, FDS and Novell eDirectory are all based on Netscapes DS,
Uh, eDirectory is the current name for NDS, which came out with Netware 4 in 1993, before Netscape was even a company.
A side benefit of Active Directory: (Score:2, Insightful)
AD (Score:2, Informative)
Microsoft has really done well with developing AD.
It's just honestly the best product out there currently.
Support (Score:3, Insightful)
You can configure a Samba server against LDAP and have everything authenticate agaist that. Your biggest pitfall is going to be finding support for the configuration. You have to consider "what if the IT Admin get's hit by a bus, who's going to support this configuration". With Active Directory you can flip open a phonebook and find a dozen local places that will support it; that's not the case with the Samba/LDAP configuration.
AD is what MS got very very very close to "Right" (Score:2)
Ad is very nice, we use it for Auth in a mixed env as well. I work in QA, the way that I've actually got mine setup is ADS run by Corp, FDS run by QA. FDS has Pass Though Authentication turned on.
You may want to checkout Fedora Directory Server and FreeIPA combo for linux/unix solutions
Start with SQL (Score:3, Interesting)
Yes, SQL. If you keep your raw data in SQL, it is easy to export data to any format you might need now or in the future. LDAP gets you a long way, but you will sooner or later end up with several apps that don't support it. The result is horrible password sync hacks, multiple passwords per user, etc.
The idea is to put raw user info in SQL, including their clear-text password. Of course, lock down that SQL server like you've never locked down anything before! It should have a very limited interface for updating user data. Next, export user data to relevant external databases such as LDAP, NIS, SASL, that obscure sqlite app, Kerberos, DMZ services, etc, and you'll have much less pain keeping everything in sync.
An implementation of this scheme is running on many of the biggest universities in Norway, and is called Cerebrum, http://www.cerebrum.usit.uio.no/english.html [usit.uio.no]. User administration happens through a frontend interface appropriately named BOFH, where users and admins can change data in a secure manner. Users can change certain of their own attributes, while admins have more power. It's worth checking out (although their sf.net wiki seems to be down at the moment, unfortunately).
Re: (Score:2, Interesting)
+1 to this. Extremely flexible.
We do all of this, except for plain text passwords in tables.
We highly recommend encrypting, or completely eliminating, plaintext passwords. Instead, create and store the required hashes (ssha, etc.) for various bits and pieces when you create a user, or the user changes their password.
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Yes, SQL. If you keep your raw data in SQL, it is easy to export data to any format you might need now or in the future.
slapcat > myldaptree.ldiff
Done. You now have an Ldiff file that can be re-imported directly, or parsed quite easily, not sure why Exporting seems difficult?
LDAP gets you a long way, but you will sooner or later end up with several apps that don't support it. The result is horrible password sync hacks, multiple passwords per user, etc.
gssapi/SASL, or if its a horribly broken ap that doesnt do that either, its trivial to write an authorize/authenticate plugin for it, just about everything supports LDAP though, or "AD" which is usually LDAP with the MS schema in mind that can be bent to use a normal LDAP directory instead. Password sync (to get the broken NT4/LANMAN and KRB5 pas
emoticons (Score:2)
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Hear me out (Score:5, Informative)
Its going to sound like blasphemy here on slashdot, but I strongly recommend one master ActiveDirectory server with Services for Unix installed. You can manage everything from the nice pretty windows GUI, have perfect windows support and using pam_krb5 and nss_ldap (I use them in FreeBSD, I believe both of which were originally for linux, not sure they would be the best for it) for pulling all your user information from AD. Services for UNIX adds tabs to the important objects in the ActiveDirectory UI to let you edit the unix attributes.
Combine nss_ldap, pam_krb5, sasl with kerberose auth, and samba 3 or newer, the kerberos auth module for Apache and you can have complete and total authentication based on ActiveDirectory with a very nice GUI, and you can still use standard ldap tools to work with the directory if you want. Samba will do kerberos with windows beautifully at this point, just make sure you keep eveything time synced. Even does all the 'single signon' stuff for websites.
You end up using a great authentication mechanism on your unix AND windows hosts (kerberos is king). The only catch that may or may not apply to other OSes, but it definately bit me in FreeBSD 6, FBSD wants to use UDP for all its kerberos communications which is normally fine, but once you get a user with a large collection of kerberos data, in my case, lots of groups either directly or via nesting, then the packets become too large for a single UDP datagram and FBSD is too stupid to switch to TCP on its on. My solution was simply to block all UDP port 88 requests in and out of my FBSD boxes so they immediately fail over to TCP (not, you have to return ICMP errors, not just drop packets or it'll just hang as it doesn't know the packet can't be sent).
Not sure if Linux's kerberos implementation supports forcing TCP in krb5.conf. FreeBSD is SUPPOSED to, but older version certainly don't.
I know that no one likes MS and thinks they are evil, but I've been VERY happy using AD. We have two Win2k3 machines that serves ActiveDirectory, basically a primary and backup domain controller in the old MS NTDOMAIN language. Works awesome. If you throw in the MS certificate server on your AD server, then you also have a nice way to make internal SSL certificates with full revokation support and all that neat stuff so you can make internal certs all day long and the since your Windows machines are part of the ActiveDirectory, it pushes its root cert to all your windows boxes meaning you don't have to do crap to make them fully authenticated certs for your windows machines.
With far less effort than any other directory server you can have full single sign on support, good authentication, and an easy to use interface in which you can delegate control to various folks outside your IT department and let them use the AD manager for windows (on xp or whatever) to manage the department they need to if you want. You can auth pretty much EVERY modern OS this way. Hell if you want to you can run the servers on Unix (OpenLDAP/MIT Kerberos) for backup or for serving client requests and just isolate the windows machine as the master if you want.
Okay, now I sound like a total fanboy, please don't hate, but it really is a good setup. The main reason being, from my point of view, the setup and most importantly, the administration of ActiveDirectory and Services for UNIX are FAR above and beyond anything the F/OSS world offers. Sad, but true. I imagine you could probably get good support from Novell eDirectory as its tools are pretty good when they work, haven't used them since 6.0 when all their Java apps were asstastic, but I was only admining the leaf node of a tree with a few hundred thousand accounts in it (State of Georgia was using eDirectory a few years back, all their employees are in it, may have changed by now), so it may work better in smaller setups. All things considered it didn't do bad there, was just far too slow for editing my own subtree as we had to wait on updates to be pushed back up the tree bef
FreeIPA, Apple OD, Gosa2, Novell eDirectory, FDS (Score:2, Informative)
I am with this task as well.
Since we need to support Kerberos, I had some difficulties to install OpenLDAP and manage the Kerberos and integrate with Samba and AFP.
Our servers are 80% Linux and 20% Windows,.
Our clients are 90% Mac, 9% Windows and 1% Linuxes
I have messing with the follwoing solutions without much sucesse. They are all good, but they are NOT READY yet. Maybe Novell eDirectory, but I think it is too big and kind of expensive.
I really don't like Microsoft, so we are avoiding AD and avoiding sup
Re:Stick with OpenLDAP ... (Score:4, Insightful)
First off, AD does provide LDAP services, it is ActiveDIRECTORY after all.
Second, every OSS app out there pretty much lets you modify the schema it expects from the server, meaning making it talk to an ActiveDirectory server is just a matter of properly setting up the schema. Hell most apps now days already have an example config for talking to a stock ActiveDirectory, but you're better off with AD + Services for Unix so you get AD and Unix UID/GID administration in one pretty point and clicky interface.
Other than having a more flexible schema, since it doesn't assume you need to talk to windows, its inferior to AD in just about every other way, excluding price, where of course it beats the shit out of AD :)
If your last two startups were made easier by not using AD, you have incompetent admins who don't actually understand ldap or kerberos.
With openldap you get a directory, which CAN be used to authenticate, but thats not what you should be doing. Kerberos is accepted everywhere as the best authentication system to use in an organization, hands down, Unix OR windows. With AD you get both. Which means instead of using your crappy 'bind to auth' or 'bind as someone then query to auth' and 'hopefully we remembered to use SSL everywhere that needs auth', with AD you get LDAP + kerberos for auth, best of both worlds.
AD allows you to manage users with those same applications, host or web based as it support LDAP perfectly so OpenLDAP doesn't have anything on it there.
Fourth, you can just make samba join your activedirectory server instead of making it pretend to be one and dealing with all the quirks that goes with that if you have anything beyond the most simple of setups.
Want samba to join ads? Install samba 3 or newer, install a time sync utility if you don't already have one, type:
net ads join
Follow prompts, done.
Go the next step and tell samba to generate a keytab for kerberos for you and be happy as now you can start using kerberos for other services rather a cobbled together bunch of hacks to bindauth or queryauth off the ldap server.
Me thinks you don't really have any actual experience with or an idea what AD is. AD is NOT NTDOMAINS, even though an AD server is capable of providing backwards compatibility, it is not required and if you're using not using anything older than XP and unix machines it should be turned off.
OpenLDAP is only a partial replacement for ActiveDirectory, and really is the WRONG way to do authentication. MS didn't invent kerberos, but switching to it was one of those 'Okay, you win, we're on the bandwagon with your protocols' moments that you should actually thank them for and look into. Stop hating and educate yourself.
What OpenLDAP wins at, hands down, is of course, cost. But its really silly to say that its more flexible or more reliable (which, btw availability and uptime mean the same thing here).
Do you want to use a bunch of hacks to make your windows machines authenticate, or would you rather use a system that supports everyone natively and completely, Windows AND Unix (including OSX)? Personally I went with AD so I can just do everything natively, with Services for UNIX the thing will even function as a NIS (maybe NIS+, I don't use that part) server if you've got old boxes that you need to pull into the group.
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