Notes from the Field #2: Catalyst 3750 SW upgrade and ‘does not support the same feature set’

The Catalyst 3750 by default prevents you from changing feature sets (i.e., going from IP Base to IP Services or vice versa) when upgrading the IOS using the archive download-sw command.

Error: The image in the archive which would be used to upgrade
Error: system number 1 does not support the same feature set.

To overcome this, add the /allow-feature-upgrade argument to your archive download-sw command:

archive download-sw /allow-feature-upgrade /overwrite tftp://10.1.15.141/c3750-ipserviceslmk9-tar.122-55.SE4.tar

Notes from the Field #1: ASA

When performing a factory reset (configure factory from global configuration mode), the license key persists and so does enable/console passwords.

It’s also wise to perform a reload after doing a factory reset. Whilst it doesn’t seem required, one of the subinterfaces I had set configured on the ASA to act as a gateway for a subnet was dropping packets, without logging anything.

Exchange 2007/2010 Distribution groups and unauthenticated users

This is going to be a very brief post. I’m currently setting up Nagios to do some network monitoring at my place of work. Several weeks ago, I had upgraded our Exchange 2003 mail server to Exchange 2010. Our e-mail distribution groups were all mail-enabled security groups with global scope. I hadn’t bothered to upgrade them yet to mail-enabled security group with universal scope. I initially had Nagios sending notifications to a particular pre-existing mail-enabled security group that was created when Exchange 2003 was in production. Notifications flowed to members of the distribution group correctly… However, when I changed the contact in Nagios to e-mail a new mail-enabled security group with universal scope, the notifications stopped working. The MTA on the Nagios box, Postfix, was not getting any ‘bounce’ messages from the Exchange server. As far as Postfix was concerned, the message was being delivered. I turned on verbose logging on the hub transport receive connector and verified that the Exchange server was indeed telling the MTA that it had queued the message for delivery. After several minutes of Googling and head scratching I learnt that by default, distribution groups (security or otherwise) don’t accept mail from unauthenticated users. Whilst I thought I had successfully configured the Nagios box to perform TLS authentication, it wasn’t working correctly (the hub transport receive connector log alerted me to this). To resolve this issue, I simply allowed unauthenticated users to deliver mail to the distribution group.

To allow a distribution group to accept mail from unauthenticated users:

1. Open Exchange Management Console.
2. Locate the distribution group in question under Recipient Configuration.
3. Right-click on the group and click Properties.
4. Click on the Mail Flow Settings tab.
5. Select the Mail Delivery Restrictions option and click the Properties button.
6. In the Mail Delivery Restrictions dialog box, uncheck ‘Require that all senders are authenticated’ and click OK on any open dialog boxes to save changes.

Welcome!

Welcome to my blog. My name is Joshua Morgan and I’m currently 20 years old. I currently work in the education industry as a Network Administrator. I run the day-to-day operations of the network, including the servers, virtualization (via Hyper-V), storage, routing, switching, firewalls, etc. Within the next few months I’m hoping to move on and get a job as a Network Engineer, for either a consulting/systems integrator (that would be ideal) or an enterprise…

I’ve created this blog for several reasons. First, I want somewhere I can store my notes of various things I come across or that I’m currently learning (I’m always studying for different IT-related certifications). I also want somewhere I can point potential employers to so that they can see I know what I’m talking about. Hopefully, some other readers will find it interesting or otherwise useful too.

Outside of IT, I’m currently also learning to fly, so you might find some notes on here pertaining to that too.