Specifications

Americas Headquarters:
Cisco Systems, Inc., 170 West Tasman Drive, San Jose, CA 95134-1706 USA
Upgrading the Cisco IOS Software
This module describes how to upgrade the Cisco Internet Operating System (IOS) software image on the
following hardware:
• Cisco 3900 series ISRs
• Cisco 2900 series ISRs
• Cisco 1900 series ISRs
• Cisco 1941W Wireless Device
This module contains the following sections:
• Restrictions for Upgrading the System Image, page 1
• Information About Upgrading the System Image, page 2
• How to Upgrade the Cisco IOS Image, page 3
• How to Upgrade the IOS Image on the Access Point, page 23
• Additional References, page 26
Restrictions for Upgrading the System Image
• Cisco 3900 series, 2900 series, and 1900 series integrated services routers (ISRs) download images
to new Advanced Capability CompactFlash (CF) memory cards. Legacy CF will not operate in
Cisco 3900 series, 2900 series, and 1900 series ISRs. When legacy CF is inserted, the following
error message appears:
WARNING: Unsupported compact flash detected. Use of this card during normal operation can
impact and severely degrade performance of the system. Please use supported compact flash cards
only.
• Slot0 is the default CF slot. CF in Slot0 stores system image, configuration, and data files. CF must
be present in this slot for the router to boot and perform normal file operations.
• Cisco IOS images for the access point download images to the CF embedded on the access point.