Networking

Exchange 2007 needs command line to set FQDN of external host name on Send Connector

Published
by
Greg
on August 22, 2008
in Internet, Networking and Windows Server
. 0 Comments

In Exchange 2007, you have a nice little GUI to set your FQDN on your Send Connector. (Mine is called Outbound, as shown below.)

You can see my FQDN, set under the Hub Transport/Send Connectors of the Exchange Management Console.

However, if you send mail out to an external address, you’ll notice in the headers that your internal server name is still listed! What!? What’s the point of the GUI?

You have top open Exchange Management Shell, and type in a command to solve this. It’s easy.

As shown above, you just type in the command:

set-sendconnector “Outbound” –fqdn mail.1stbyte.com

Replace “outbound” with the name of your send connector, and of course, change to your own FQDN, not mine.

It will come back in error, or success. If success, you can check your headers on and external account right away.

Have fun!

DFS links to shares on Windows XP SP2 do not work on local system

Published
by
Greg
on April 18, 2008
in Networking, PC Repair, Windows Server and Windows XP
. 0 Comments

Well for the larger businesses out there, this may not be a useful tip. But for those of us that support small networks, like less than 50 or even 10 systems, utilizing shares on workstations is sometimes needed. For example, I have servers in most all of my networks, and their hard drives are fairly large, but I don’t want to save all my downloads and application CD’s on the server. With newer workstations loaded with larger drives than servers sometimes, I’d rather make use of that space there. Not with the main, business critical data, but only things that are not needed for backups or maybe read only archives. These 500+ GB drives give us a ton of space, and when you only have less than 10 people accessing this data periodically, this makes perfect sense. Constant read/write access with lots of users would require the server, rarely accessed stuff goes on a workstation.

Here’s the problem I ran into though. I like to use DFS and create a single shared, mapped drive for all the users. In there I might have a couple shares pointing to workstations. On XP SP2, this works fine, EXCEPT if you are accessing the DFS link from the system where the share resides. You will get an Access Denied error, even with all the correct permissions.

Here’s a registry fix that will overcome the issue.
(Remember, use the registry at your own risk. Back it up if you must. Heck, backup your whole system!)

Open this key on the XP system:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Mup\Parameters

Add a DWORD value:

EnableDfsLoopbackTargets

Change its value to 1.

Reboot the system.

Your share should now be working from DFS mapped drive from the local system. (the local system where the share is located.)

Find an email address that already exists in Active Directory

Published
by
Greg
on April 14, 2008
in Networking and Windows Server
. 0 Comments

So you went to add a new address to a user account in Active Directory, and you got an error that this address already exists? Sucks huh? Especially when you don’t know where it could be? Here’s one way to track it down.

On your domain root in AD Users and Computers, right click, select Find. Select Custom Search, click the Advanced tab, and enter an LDAP query like so:

proxyaddresses=smtp:emailaddress@youwanttofind.com

(I am assuming you are not a complete NEWB and you know you should replace that email with the one you want.)

Then click the Find Now button. You should see a in the results below any object that may have this address on it.

New account does not appear in Global Address List but does in All Users

Published
by
Greg
on March 27, 2008
in Internet, Networking and Windows Server
. 1 Comment

I’ve run into this a few times, thought I’d record the solution for once so I remember it.

After adding a new user account, the user does not show up in Outlook’s Global Address List, but does show in All Users. (If you click “To” in a new message, for example, and in the Select Names windows under “Show names from the:” drop down, you select All Users.) Even if I go into Active Directory Sites and Services and manually force replication it does not work. (under the NTDS Settings for each server) Normally, I would even go into Recipient Update Services and manually update, but this does not work either.

I found out that if you have Outlook in Cached Exchange Mode, the Global Address List does not update for up to 24 hours. I don’t know the details on that, but I can force it to update. This is on a per-machine basis, so doing this across the whole network won’t work. (Although, there may be a way to do this, I just don’t know how.)

Go into Outlook, go to Tools, Send/Receive, then click Download Address Book. Make sure you have Global Address List under the Choose Address Book drop down, and click OK. Problem solved.

By the way, I am using Exchange 2003 and Outlook 2003.

Folder redirection user permissions block access to Administrators

Published
by
Greg
on March 19, 2008
in Networking, Security and Windows Server
. 0 Comments

When using Folder Redirection on a Windows 2003 server, the default policy is allow only ownership and permissions to the user. No admin account would have access to this folder. For example, you create a Group Policy to redirect user’s My Documents folders to a home directory on the server. Once a user logs on and this policy is applied, the folder is created with ownership of the user only, and file permissions granted for that user only, too.

This has presented a big problem for me, having come from Windows 2000, where this was not the case. As you might guess, when only the user has permissions specified, no administrator can get access to this folder for backup purposes. Our backups always failed.

Well then, on Windows 2003 Server, two default policies are in place making the user’s folders more secure. Nice, but I don’t care. I want backup rights by default. Go into the Group Policy where you would like to define the new policy. I made a new Organizational Unit and put all my computers in there, so I could define the policy at a lower level, instead of at the domain level. Once into and editing you policy, drill down to here:
Computer Configuration –
    Administrative Templates -
        System –
            User Profiles –

In here look for these two policies and enable them:
“Do not check for user ownership of Roaming Profile Folders”
“Add the Administrators security group to roaming user profiles”

Now this will allow Windows 2003 to behave more like Windows 2000 on the redirected folders. Unfortunately, there is one issue. It does not change permissions on previously created folders, only on newly created folders. That’s a pain, but not that big a deal, because I can probably script some folder moves and recreate them.

Resetting NTFS permissions are not taking effect on child objects

Published
by
Greg
on March 19, 2008
in Networking, Security and Windows Server
. 0 Comments

Recently I went to reset a user’s home directory permissions on the server to allow them full control over each file/folder in their home directory. I setup all the normal accounts and of course the actual user account, with Full Control. I then went into Advanced and selected “Replace permission entries on all child objects” and hit apply.

This seemed to work fine, except the user complained that they could not access the documents in certain subfolders. When I checked those subfolders, the permissions were correct, except for her account had no permissions specified. Essentially this means, no perms, no access. So I tried again, same result.

The solution was simple, though, I can’t figure out why this was configured this way. At the root folder you wish to start inheritance, go into advanced under security on that folder. Go into Advanced again, and under Permissions, highlight the user in question, and click Edit. Under the detailed Permission Entry window, at the very bottom is a checkbox for:

“Apply these permissions to objects and/or containers within this container only.”

Uncheck that! And apply the permissions once more. All child objects should now have all the correct permissions! Yay!

I don’t understand why this is set this way. Is there a Group Policy in place I don’t know about? Did a previous IT guy change that? At least I have a solution. J

IE7 fails to automatically authenticate with enable integrated windows authentication checked

Published
by
Greg
on March 15, 2008
in Internet, Networking and Web Design
. 1 Comment

In Internet Explorer 7, Tools, Internet Options, Advanced tab. The checkbox for “enable integrated windows authentication” is very confusing. You would think this means “just log me in with my windows credentials”, but no, there’s more to it than that. And what I found was, it simply enables “Negotiate”. It set’s this registry key to 1:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\EnableNegotiate

After some research, this actually means that IE will negotiate between NTLM or Kerberos authentication. In some situations, Kerberos will fail. I don’t understand well enough to explain this one. But that’s ok, because the point of all this is… I want IE to authenticate automatically on my Intranet! Anyway, if you uncheck this setting in IE, it will set Negotiate to disabled. (0) If Negotiate is disabled, IE will use NTLM by default. BAM! I can login automatically.

Wouldn’t it be much more helpful if Microsoft had labeled that for what it was? Like: Negotiate Kerberos or NTLM Authentication.

Word of caution… some Intranet apps might depend on Kerberos, so this might cause more problems down the road of you disable this on all your client systems.

Another note… IE6, as I understand it, does not behave this way. It has a similar setting to enable windows authentication and I believe it uses NTLM by default. I HAVE NOT TESTED THIS, and I don’t know for sure if this is true, but according to my Googling, this is the case.

I found this site with info regarding EnableNegotiate:

http://ie7triage.spaces.live.com/blog/cns!3B6634EF5458F389!422.entry

 

Here’s another blog you might find useful:

http://blog.super-networking.net/systems/internet-explorer-enable-integrated-windows-authentication/

 

 

 

Is a hardware firewall really a software firewall anyway?

Published
by
Greg
on March 5, 2008
in Internet, Linux, Networking and Security
. 3 Comments

I love how people always say that a software firewall like IPCop is a “lesser” product than a hardware system. I ran into one site speaking of Netsentron as a hardware solution. I’d also include Endian Firewall and Untangle when we talk about a “linux based hardware firewall”. Well here’s my thought. These systems offer a hardware solution, but aren’t these products really the same thing as the downloaded software version they provide? And if so, these products are really only a “hardware/software bundle”, right? (I think they actually advertise them this way anyway, but my gripe is with all those techs out there under the notion that these are real hardware based products.)

I can’t comment on any Cisco or Sonicwall, hardware firewalls, because I have not used any of them. But are these also just software running on hardware? And the main thing I’ve heard from security people about the lesser quality software products is that they are not good at defending against DOS attacks. Is this really true? Even if so, in the last 10 years I’ve ran some sort of Linux based firewall, whether home-brewed or special firewall distribution, I’ve not once had a break in. I’ve not once had a DOD attack. (THIS IS NOT AN INVITATION!)

Now, I have had a DOD attack directly on and Exchange or IIS server that was port forwarded directly to the Internet. Not pretty! Which is a big reason why I don’t run these systems directly anymore. But this is off topic. (maybe another blog coming!)

I’ll do some of my own research, but maybe if someone out there can shed some light on the deficiencies of a Linux firewall, in particular IPCop or Smoothwall. For my use, IPCop with a few addons, make for a fantastic filtering firewall, provided we pick good hardware to run it, and configure it properly. Is Sonicwall truly better at providing security?

Ah, just thinking out loud again. I am sure someone out there will give me hell for saying things like this. I am not a security expert, not even close. But, sometimes I just wonder about things… J

OMA Service Unavailable

Published
by
Greg
on December 17, 2007
in Internet, Networking and Windows Server
. 0 Comments

I found a ton of help on Google for this “Service Unavailable” issue on the OMA virtual directory for Exchange 2003. Unfortunately, this was not something readily available. Several sites will explain the proper config for all the virtual folders in IIS, which you should obviously follow, but they don’t mention one little thing… OMA uses ASP.net 1.1. If you go into the OMA properties in IIS, change it from ASP.net 2 to ASP.net 1.1. After that, it all worked beautifully!

Oh, and by the way, I ran into this issue while setting up some Windows Mobile devices with ActiveSync and Direct Push at a couple clients, one was running IIS5 on Windows 2000, and the most recent was running IIS6 on the Windows 2003. The solution was the same on both of them.

IPCop 1.4.15 with PPTPd would not run because of libpcap link

Published
by
Greg
on October 3, 2007
in Linux, Networking, Security and Windows Vista
. 0 Comments

I fought with this one for a while, like several hours. I installed the pptp addon for IPCop, which, by the way, you must Google for. I installed version 0.2.9 (pptpd_0.2.9.tar.gz) and found that on a forum somewhere. If you go to the addon’s from IPCop, you will only find 0.2.6, and that wont work with 1.4.13 or higher. (I might have that version a bit off, but I think that’s right) So Google for that file and you should find the file and ftp server IP. I don’t want to provide that, because I don’t have permission to do so.

Anyway, back to the problem. The pptp addon installed just fine on IPCop, and the admin web gui showed the correct items. I could not, however, get Windows to connect. I always got a 619 error, like that is helpful! On the IPCop /var/log/messages, I found this:
pptpd[5740]: GRE: read(fd=5,buffer=804dc00,len=8196) from PTY failed: status = -1 error = Input/output error

You can see the details on the pptpclient help page:

http://pptpclient.sourceforge.net/howto-diagnosis.phtml#read_eproto

 

I didn’t know how to do their troubleshooting, especially on IPCop. But then it occurred to me, find pppd, and ask it for help!

I ran this: /opt/pptp/sbin/pppd –help
Returned: /opt/pptp/sbin/pppd: error while loading shared libraries: libpcap.so.0.8.3: cannot open shared object file: No such file or directory

Ah-HA!!!

Run this on IPCop 1.4.15 while in the /usr/lib directory: ln -s libpcap.so.0.9.5 libpcap.so.0.8.3

BINGO! Windows can connect! From Vista no less!

Oh, and I know that PPTP is not the best as far as security goes, but it is the only thing I can use. I am running several Wifi Palm devices with a PPTP client on them for Hotsyncing on the Internet. I realize there is another product available that uses IPSec, but that is quite expensive per device. Plus that solution might run into a lot more hassle for the users while on the road trying to connect over hotspots, because IPSec may be blocked. PPTP is just more compatible. I’d really prefer to have an SSL based VPN on the Palm, but I don’t know of one available. So, for now, I’ll at least suffer with PPTP instead of opening my hotsync up to the world. Not perfect, but I can lock down the connection with IPcop too. (sounds like another blog… J )