Release Notes for Cisco IOS Release 15.1M&T
First Published: March 26, 2010
Last Updated: October 24, 2016
Release: Cisco IOS Release 15.1(4)M12a
These release notes support Cisco IOS Release 15.1M&T up to and including Cisco IOS Release 15.1(4)M12a. They are updated to describe new features and related documents.
Cisco IOS Release 15.1M&T integrates a portfolio of over 2000 key capabilities that span multiple technology areas, including Security, Voice, Multiprotocol Label Switching (MPLS), IP Services, and Embedded Management.
Key highlights of Cisco IOS Release 15.1M&T include the following:
- Ideal for very latest features and hardware support.
- Incorporates features and hardware support previously delivered in Cisco IOS Release 15.0(1)M and prior releases.
- Positioned for short deployment cycle (until next Extended Maintenance release becomes available).
- Standard maintenance bug-fix rebuild for 13 months, plus an additional 6 months support for security/vulnerability issues such as Cisco Product Security Incident Response Team (PSIRT) advisories (see http://www.cisco.com/en/US/products/products_security_advisories_listing.html).
- Rebuilds of Cisco IOS Release 15.1M&T that contain bug fixes only.
This document contains the following sections:
Cross-Platform System Requirements
This section describes the system requirements for Cisco IOS Release 15.1M&T and includes the following sections:
Supported Hardware Platforms
Cisco IOS Release 15.1M&T supports the following Cisco hardware platforms:
- Cisco 800 series routers
- Cisco 1800 series routers
- Cisco 1900 series integrated services routers
- Cisco 2800 series integrated services routers
- Cisco 2900 series integrated services routers
- Cisco 3800 series integrated services routers
- Cisco 3900 series integrated services routers
- Cisco AS5350XM universal gateways
- Cisco AS5400XM universal gateways
- Cisco CGR 2000 series
- Cisco IAD2430 series integrated access devices
- Cisco IAD2801 series integrated access devices
- Cisco unified communications 500 series
- Cisco VG200 series analog voice gateways
- Cisco VGD 1 T3 voice gateways
Note Cisco 7200 series and Cisco 7301 routers will continue to be supported in Cisco IOS 15.n(n)M releases. Only the Cisco IOS 15.n(n)T releases will not support the Cisco 7200 series and Cisco 7301 routers.
For more information about the platforms supported in Cisco IOS Release 15.1M&T, see the “Platform-Specific Information” section.
Determining Your Software Version
To determine the version of Cisco IOS software that is currently running on your Cisco network device, log in to the device and enter the show version user EXEC command:
Cisco Internetwork Operating System Software IOS (tm)
15.1 Software (c2430-is-mz), Version 15.1(1)T, RELEASE SOFTWARE
To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:
If Cisco MIB Locator does not support the MIB information that you need, you can also obtain a list of supported MIBs and download MIBs from the Cisco MIBs page at the following URL:
To access Cisco MIB Locator, you must have an account on Cisco.com. If you have forgotten or lost your account information, send a blank e-mail to email@example.com. An automatic check will verify that your e-mail address is registered with Cisco.com. If the check is successful, account details with a new random password will be e-mailed to you. Qualified users can establish an account on Cisco.com by following the directions found at this URL: