Asr1000-rommon.173-1r.spa.pkg Link
asr1000-rommon.173-1r.spa.pkg is a critical ROM Monitor (ROMMON) firmware package designed specifically for the Cisco ASR 1000 Series Aggregation Services Routers. It acts as the router's bootloader, responsible for hardware initialization and launching the Cisco IOS XE operating system The Core Role of ROMMON
ROMMON is a specialized firmware that resides in the router’s read-only memory (ROM) and runs immediately upon power-up or reset. Its primary functions include: Hardware Diagnostics
: Initializing the processor hardware and performing power-on self-tests (POST) Bootloading
: Locating and loading the Cisco IOS XE software image from the bootflash or via TFTP Disaster Recovery
: Providing a low-level environment to recover from lost passwords, corrupted software images, or hardware failures Separation of Powers
: It is a standalone program; the router is either in ROMMON mode or IOS XE mode, but never both at the same time Significance of Version 17.3(1r)
The 17.3(1r) release is a major milestone for the ASR 1000 series, often required for compatibility with modern Cisco IOS XE 17.x software branches A critical characteristic of this version is its irreversibility
on specific hardware platforms. Once you upgrade the ROMMON to 17.3(1r) on the following devices, you cannot revert to an earlier version ASR 1001-X ASR 1001-HX ASR 1002-HX
For other platforms in the ASR 1000 series, such as the ASR 1004 or 1006, reverting is still technically permitted if needed Upgrade Mechanics and Best Practices The upgrade process involves using the upgrade rom-monitor command in privileged EXEC mode . Key considerations include: Prerequisites : Ensure you have verified the MD5 signature of the asr1000-rommon.173-1r.spa.pkg
file to avoid signature mismatch errors that can halt the process
: While it is possible to upgrade ROMMON and the IOS XE image simultaneously, community consensus and official guides often recommend splitting these tasks to better isolate potential issues : The command typically follows the syntax:
upgrade rom-monitor filename bootflash:asr1000-rommon.173-1r.spa.pkg all Cisco Community
: Never interrupt power during the upgrade. A failure during this stage can render the hardware component (RP, ESP, or SIP) unbootable Cisco Community For detailed technical steps, refer to the official Cisco ASR 1000 Series ROMmon Upgrade Guide Do you need help with the specific command syntax
to verify your current version before proceeding with the upgrade?
To upgrade your Cisco ASR 1000 series router using the asr1000-rommon.173-1r.spa.pkg file, follow this consolidated guide. This procedure is typically required when moving to IOS-XE 17.x releases. 1. Preparation & File Transfer
Before starting, ensure you have the correct ROMMON package and your target IOS-XE image (e.g., asr1001x-universalk9.17.06.03a.SPA.bin).
Transfer files: Use TFTP, SCP, or a USB drive to move the package to the router's bootflash. asr1000-rommon
copy tftp:// Use code with caution. Copied to clipboard
Verify Integrity: Always check the MD5 or SHA512 hash to prevent corruption. verify /md5 bootflash:asr1000-rommon.173-1r.SPA.pkg Use code with caution. Copied to clipboard 2. ROMMON Upgrade Process
This step updates the bootstrap software. It is often recommended to do this before or alongside the IOS-XE upgrade.
Run the upgrade command: Use the all keyword to ensure all relevant components (like line cards or RP) are updated.
upgrade rom-monitor filename bootflash:asr1000-rommon.173-1r.SPA.pkg all Use code with caution. Copied to clipboard
Wait for completion: The router will indicate when the upgrade is finished. Do not power cycle during this process.
Save and Reload: You must reload the router for the new ROMMON to take effect. write memory reload Use code with caution. Copied to clipboard 3. Verification After the reload, confirm the new version is active. Check Platform Status: show platform Use code with caution. Copied to clipboard Check ROMMON Version: show rom-monitor slot R0 (or show version) Use code with caution. Copied to clipboard 4. Proceed to IOS-XE Upgrade (Optional but Recommended)
Once the ROMMON is at 17.3(1r), you can safely proceed with an Install Mode upgrade to your target 17.x IOS-XE version. Install Command: What is this file
install add file bootflash: Use code with caution. Copied to clipboard Troubleshooting Notes
Stuck Upgrade: If the version doesn't change after a reload, ensure you used the all keyword and that the hardware (e.g., RP1 vs RP2) supports this specific package.
Install vs. Bundle Mode: Cisco TAC generally recommends Install Mode for faster boot times and better resource management on ASR platforms.
What is this file?
The filename follows the Cisco ASR 1000 naming convention, breaking down as follows:
asr1000: Indicates the hardware platform (ASR 1000 Series).rommon: This is the ROM Monitor firmware. Think of this as the "BIOS" or "bootstrap" for the router. It is the first code that runs when the device powers on, responsible for hardware initialization and loading the main IOS-XE operating system.173-1r: This represents the firmware version number (Release 17.3, Version 1r).spa.pkg: Indicates this package relates to the Shared Port Adapter (SPA) architecture or the specific carrier card/sub-slot hardware initialization within the chassis.
3. Why Would You Need to Upgrade ROMMON?
Production routers often run for years without a ROMMON update. However, specific scenarios demand it:
| Scenario | Why Upgrade to 17.3(1r) | |----------|--------------------------| | Hardware replacement | Newer supervisor or RP modules ship with older ROMMON. Upgrade ensures feature parity. | | IOS-XE upgrade beyond 17.9 | Newer bootloaders need improved memory initialization and SHA-512 image verification. | | Security vulnerabilities | Fixes for ROM-based attacks (e.g., ROMMON-1 bypass). | | USB boot support | Later ROMMON versions fix USB enumeration and file system read/write issues. | | TPM (Trusted Platform Module) | Required for secure boot and hardware anchoring. |
Without this upgrade, you may see the following failure when booting a new IOS-XE:
%ROMMON-IMG-INVALID: Image checksum failed
%ROMMON-BOOT-FAIL: No valid boot image, falling back to rommon
Risks and precautions
- ROMMON upgrades are low-level and can render a router unbootable if interrupted.
- Always verify compatibility between ROMMON and your IOS‑XE train and hardware model.
- Back up existing ROMMON and configuration, and ensure console access (not just SSH) to recover if network services fail.
- Follow maintenance windows and have a recovery plan (local image on USB/flash, alternate boot method).
4. Which Hardware Supports This Version?
ROMMON versions are tied to the Route Processor model:
| RP Model | Supported ROMMON | Notes | |----------|----------------|-------| | RP1 (ASR1000-RP1) | Up to 152-1r | Not compatible with 173-1r – different CPU architecture | | RP2 (ASR1000-RP2) | 173-1r and later | Fully compatible | | RP3 (ASR1000-RP3) | 173-1r baseline, but later versions exist | Works, but newer hardware may require 174+ | | ESP100/200/ESP3 | N/A | ESPs have separate firmware (not updated via this package) |
Critical constraint: Do not attempt to load this ROMMON on an ASR1001-X or 1002-HX without checking the minimum ROMMON requirement for its IOS-XE release.
Common filename meaning
- asr1000 — target platform (ASR 1000 Series).
- rommon — ROM Monitor image.
- 173 — aligns with IOS‑XE 17.3 train compatibility.
- 1r — internal build or revision identifier.
- spa.pkg — packaged installer format used by Cisco for ROMMON/SP/firmware bundles.
