Having a clear understanding of the image type and its expected configuration interface (serial console) is critical before you start repacking. If you attempt to use an image that expects a graphical interface in a serial‑only environment, the process will fail.
This step is the most important. You must acquire the specific disk image file ( .qcow2 ) that has the designation in its name. A valid example is: csr1000v-universalk9.17.03.04a-serial.qcow2 .
qemu-system-x86_64: -cdrom csr1000v-universalk9.16.09.06.iso: could not open disk image
: The most effective way to reduce image size is to zero out free space inside the VM before repacking . Boot the CSR1000v and run: csr1000vucmk916121bserialqcow2 repack best
guest> exit Router# reload
If you are staging this image for a platform like EVE-NG , follow these steps to properly unpack, name, and repack the image for flawless execution: 1. Prepare Your Working Directory
: Version 16.12.1b (Gibraltar train). This specific maintenance release is considered a "sweet spot" for network emulators. It provides comprehensive stability for enterprise feature sets and serves as a bridging platform for legacy routing and modern SD-WAN control planes. Having a clear understanding of the image type
The virtual image represents a milestone version of Cisco’s Cloud Services Router (CSR 1000v). Running on the IOS XE Gibraltar 16.12.1b codebase, this image natively bundles Unified Communications (UC) capabilities alongside classical routing features.
If you do not need the default large disk size, you can keep the disk small and add a secondary virtual disk later. However, for 16.x versions, keeping the default size (usually 8GB+) is recommended to avoid filesystem issues. Step 4: Verification Verify the new image: qemu-img info csr1000v-161201b-repacked.qcow2 Use code with caution. Deploying the Repacked Image (EVE-NG/GNS3)
cp csr1000vucmk916121b.qcow2 /opt/unetlab/addons/qemu/csr1000v-16.12.1b/virtioa.qcow2 You must acquire the specific disk image file (
The best feature to include in a repacked version of this image is a . This feature leverages the serial nature of the image to bypass redundant boot-time hardware checks and optimize it for low-resource lab environments. Key Capabilities:
Once verification is complete, replace the original image:
Check the current cluster allocation size and internal virtual parameters: qemu-img info csr1000v-ucmk9.16.12.1b-serial.qcow2 Use code with caution. 3. Execute the Best Repack and Compression Routine
