Release Notes for Cisco ESR6300 Routers, IOS-XE 26.1.x
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Cisco ESR6300 Routers, IOS-XE 26.1.x
Cisco ESR6300 Routers, IOS-XE 26.1.x
This release note provides information about the new features, resolved and open issues, supported software packages and information on how to obtain support and documentation.
This section provides a brief description of the new software features introduced in this release.
IOS-XE 26.1.1
Table 1. New software features for Cisco ESR6300 Routers, IOS-XE 26.1.x
| Product Impact |
Feature |
Description |
| Security |
Resilient Infrastructure |
As part of the ongoing commitment to network security, this release introduces secure alternatives to legacy commands. These updates are designed to mitigate potential risks and assist in establishing a more robust and secure operational baseline. The identified insecure commands are categorized as: • Line transport: Updates to secure remote access methods. • Device server configuration: Hardening of server-side settings. • File transfer protocols: Transitioning to encrypted transfer methods. • SNMP: Enhancements to secure management traffic. • Passwords: Strengthening authentication and credential management. • Miscellaneous: General security improvements for various system functions. The show system insecure configuration command introduced in Cisco IOS XE 17.18.2 release lists all insecure commands configured on the device. For all detected insecure configurations during device boot or upgrade, error messages are displayed. In Cisco IOS XE 26.1.1 release, all insecure CLI commands are blocked by default to strengthen your network infrastructure. If your environment requires the use of a legacy command, you must enable the system mode insecure command in global configuration mode. • Recommendation: Do not use insecure mode. This mode is temporary and will be removed in a future release. Identify and replace all insecure commands with their secure alternatives. • Upgrade behavior: If you upgrade to Cisco IOS XE 26.1.1 release with insecure commands already present in the running configuration, the system mode insecure command is automatically added to your configuration to prevent service disruption For more details, see Resilient Infrastructure IOS XE Security Warnings Reference |
IOS-XE 26.1.1
There are no new hardware features introduced in the 26.1.1 release.
Syslog Warning on Reload for SSH Hostkeys: After a device reload, you may see a syslog warning indicating insufficient SSH host key length, even if a strong RSA or EC key is configured.
Note:
● In the syslog warning message “crypto key generate rsa modulus <modulus-size> label <label-name>”, the <modulus-size> and <label-name> represent the actual modulus size and label configured on the device.
● The SSH keypair association configuration is done using the command: ip ssh ec|rsa <keypair-name>, where <keypair-name> corresponds to the keypair name configured on the device.
Example:
Warning Observed: INSECURE DYNAMIC WARNING - Module: SSH.
Command: crypto key generate rsa modulus <modulus-size> label <label-name>.
Reason: An SSH host key has been provisioned on the device with insufficient key length.
Remediation: Please provision an SSH RSA host key with minimum modulus size of 3072 bits for enhanced security.
Sub mode: exec.
Parent CLI: Not Applicable.
Warning Observed: INSECURE DYNAMIC WARNING - Module: SSH.
Command: crypto key generate ec keysize <modulus-size> label <label-name>.
Reason: An SSH host key has been provisioned on the device with insufficient key length.
Remediation: Please provision an SSH EC host key with minimum modulus size of 256 bits for enhanced security.
Sub mode: exec.
Parent CLI: Not Applicable.
If you have already configured a strong key, you can ignore the warnings that may appear during boot before the keypair association takes effect. The system applies the SSH keypair association (ip ssh ec/rsa <keypair-name>) after the boot process.
Once this configuration is active, SSH will use the correct key for secure connections.
IOS-XE 26.1.1
There are no resolved issues in this release.
You can also access the resolved caveats for this release through the Cisco Bug Search Tool.
Note: This software release may contain bug fixes first introduced in other releases. To see additional information, click the bug ID to access the Cisco Bug Search Tool.
IOS-XE 26.1.1
There are no open issues in this release.
IOS-XE 26.1.1
There are no known issues in this release.
This section provides compatibility details for cellular module modem firmware and OEM/PRI versions used in Cisco IoT routers. It includes the latest modem firmware available for each supported modem. See the Cisco Firmware Upgrade Guide for 4G LTE and 5G Cellular Modems for upgrade instructions.
Cisco IOS-XE updates do not automatically update modem firmware. You must manually check and update all modems to the latest firmware version, including any related PRI and/or OEMPRI components. Refer to the following table for the most up-to-date information.
Table 2. Cellular Module Modem Firmware for Cisco ESR 6300 Router, IOS-XE 26.1.x
| Cellular Module |
Modem |
Software download link |
| P-LTE-MNA |
WP7610 02.37.03.05 |
|
| P-LTE-LA |
EM7430 2.38.00.00 |
Generic: |
|
|
EM7430 02.33.03.00 |
Australia Telstra: |
|
|
EM7430 2.38.00.00 |
Japan: |
| P-LTEA-EA |
EM7455 02.37.0x.00 |
Generic: |
|
|
EM7455 02.39.00.00 |
Europe: |
|
|
EM7455 02.32.11.00 |
Canada: |
|
|
EM7455 02.32.11.00 |
North America ATT: |
|
|
EM7455 02.32.11.00 |
North American Sprint: |
|
|
EM7455 02.33.03.00 |
North America Verizon: |
| P-LTEAP18-GL |
LM960 32.00.1x9 |
Generic: |
|
|
LM960 32.00.1x9 |
North America: |
| P-5GS6-GL |
FN980 38.03.0202 |
|
| P-5GS6-R16SA-GL |
EM9293 02.17.08.00 |
https://software.cisco.com/download/home/286334597/type
|
This section provides information about the release packages associated with Cisco ESR6300 Router.
For latest software downloads, see the Software Download page.
Table 3. Software packages for Cisco ESR6300 Router, IOS-XE 26.1.x
| Image type |
Filename |
| Universal |
c6300-universalk9.26.01.01.SPA.bin |
Table 4. Related resources
| Document |
Description |
| Provides information about products supported by Cisco IOS-XE. |
|
| Provides information about Cisco ESR6300 Embedded Series Router. |
|
| Cisco Industrial Routers and Industrial Wireless Access Points Antenna Guide |
Provides information about Cisco Industrial Routers and Industrial Wireless Access Points. |
| Provides information about Cisco IOS XE 26 software. |
|
| Provides information about Cisco SD-WAN routers. |
|
| Provides information about Cisco IoT Field Network Director. |
|
| Provides information about Cisco Industrial Network Director. |
|
| Provides information about Smart Licensing Using Policy solutions and their deployment on IOS-XE routers. |
|
| You can submit a service request here. |
|
| Provides the most up-to-date detailed troubleshooting information. |
|
| Use CFN to browse Cisco products and find relevant features and licenses. It allows you to compare platforms, determine common features between products, and identify unique product features. The CFN also has a tab that provides a MIB Locator. |
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