Set a Budget in AWS to Avoid Costly Overages

If you’re like me and are experimenting with the AWS free tier it might be a good idea to configure a budget notification to avoid getting caught off guard by any overages.

Amazon has a great document on how to enable alerts located here, but here’s a quick guide on how to enable alerts and budget reminders.

  • First, log in to your AWS account.
  • Click the drop down menu next to your name on the top right hand of the console page and select “My Billing Dashboard.”

  • From the left hand menu select Preferences.
  • Check “Receive Free Tier Usage Alerts” and enter your email address. Click Save Preferences.

  • Next, click Budgets from the left hand menu.
  • Click Create Budget.

  • Select Cost and under Budgeted Amount select the threshold you’d like to be alerted at. For example, $0.01.

  • Under Notifications select to be alerted when costs are equal to your 100% of your Budgeted Cost and enter your email address.

  • Click Create and you should now have a new budget alert that will email you if you’re free tier is about to cost you some actual money.

Installing Telnet on Mac OS High Sierra with Homebrew

I was both sad and excited to see that Apple removed telnet from Mac OS High Sierra, excited because telnet is a nearly 40 year old protocol that is highly insecure for network management and saddened because I often have to use telnet when at client sites.

There are a few different methods you can use to bring back telnet, including copying over the binaries from a Sierra install to /usr/local/bin (as seen here)  or using a session manager like SecureCRT, but since I’ve been using Homebrew to manage a few other packages for a while now I figured I’d just go ahead and use that.

  • First install Homebrew from your terminal (warning: please don’t copy and paste code snippets from a web browser straight into your terminal, please double check your sources)
  • Run

There you have it. Run telnet by simply issuing the telnet command and the ip/port you want to connect to.


Configuring CIMC on a Cisco UCS C Server

Just got in a new UCS C server and was going through the process of configuring Cisco’s flavor of out of band management called CIMC or Cisco Integrated Management Controller. Similar to HP’s iLO or Dell’s iDrac, CIMC allows one to remotely control and manage their server via the web or SSH with handy tools like integrated KVM and ISO mounting.

  • To configure CIMC, connect your keyboard/monitor and power up the server.
  • Press F8 when the Cisco logo appears.

  • When configuring CIMC for the first time it may ask for a user/password. Try admin/password or admin/Cisco1234
  • Enter a new password when prompted.
  • Use your arrow keys to navigate the menus. Press SPACE to select/deselect options.
  • When completed press F10 to save your settings, wait 45 seconds and hit F5 to refresh and verify the settings you entered.
  • Hit ESC to exit.
  • You should now be able to access the CIMC web GUI by going to HTTPS://CIMC_IP/



Converting a Mobility Express AP into a CAPWAP AP

I was recently installing some Cisco 2802 APs and came across an issue where one of the APs  would grab a DHCP address, be reachable for a minute, and then drop off the network.

It turns out the AP having an issue actually had the Mobility Express image installed and needed to be converted to CAPWAP, even though we purchased the APs specifically with the CAPWAP SKU. Here are the troubleshooting steps I went through to convert the AP to CAPWAP.

After rebooting the AP a number of times to see if it would work, I threw a console cable on the device and saw some interesting output.

I rebooted the device again and came to this screen indicating that it was indeed in Mobility Express mode.

To reset the AP into CAPWAP mode you’ll need to enter enable mode on the CLI and enter the “ap-type capwap” command.

The AP then rebooted, got its DHCP address, and successfully connected to the controller.

Documentation from Cisco to convert an AP from Mobility Express to CAPWAP can be found here:


Upgrading IOS-XE 3.X to IOS-XE Denali 16.X

IOS-XE Denali represents Cisco’s effort to bring a single code base across their enterprise line of networking equipment, meaning the same operating system will run Catalyst, ISR, and ASR platforms.

IOS-XE 3.7 will be the “end of the track” for the 3.X train of code on Catalyst 3650/3850… so to speak.

Below are the steps I used to upgrade a 3850 from IOS-XE 03.06.03E to IOS-XE 16.3.5b Denali. The switches were in “install mode” and these steps are specific for that method. To check your mode you can issue a show version command and look under the Mode column. 3850s should come from the factory in install mode; bundle mode is similar to the older upgrade method where you boot from a monolithic bin file. More info on install mode and bundle mode can be found here.

If you’re looking to free up some space to copy over your new version you can run a software clean command to clean up any unused packages.

Copy over your new ios version via any support method (usb, tftp, scp, etc.). We’ll use the software install set of commands with the force and new flags since we’re going from 3.X up to 16.X. Once completed type yes to initiate your reload. There is some micro code upgrades that may take some time so you’re looking at about 10+ minutes of down time.