Release Notes for Cisco IE3500 Series Switches, Release 26.1.x
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Cisco IE3500 Series Switches, Release 26.1.x
Cisco IE3500 Series Switches, Release 26.1.x
This document provides Cisco IOS-XE release information for the Cisco Industrial Ethernet (IE) switches.
Cisco IE3500/IE3505 Series Switches
Cisco IE3500 and IE3505 Series Switches are ruggedized switching platforms that provide high bandwidth and high-PoE power with Cisco IOS-XE Software for industrial environments. These switches are designed to operate in harsh conditions, including temperatures from -40°C to +75°C (–40°F to 167°F), and can withstand severe shock and vibration.
These switches are designed for hardened deployments such as factory automation, smart cities, energy and process control, Intelligent Transportation Systems (ITS), energy production sites, and mining. They also provide improved scale, built-in security features, and simplified management. For more information, refer to the Datasheet.
Cisco IE3500H/IE3505H Series Switches
Cisco IE3500H and IE3505H Series Switches are the next-generation managed IP67 switches powered by Cisco IOS-XE. They are designed for deployment in harsh environments and are IP67-rated for water and dust resistance. These switches also operate in temperatures from -40°C to +75°C (-40°F to 167°F) and are built to withstand severe shock and vibration.
These switches are available with up to 24 ports. Fast Ethernet is supported through Fast Ethernet PIDs, and 1G PIDs can also operate at 100M speed. For a list of supported SFPs, refer to the Datasheet. These switches can be wall-mounted and deployed without a housing cabinet. They offer a power budget of 240W and support Power over Ethernet (PoE), PoE+, and Universal Power over Ethernet (UPOE) at 60W.
These switches provide advanced security, segmentation, and visibility for demanding industrial IoT edge deployments such as mining, rail, and manufacturing. For more information, refer to the Datasheet.
This section provides a brief description of the new software features introduced in Cisco IOS-XE 26.1.x release.
IOS-XE 26.1.1
Table 1. New software features in Cisco IOS-XE release 26.1.1
| Product Impact |
Feature |
Description |
| Security |
Resilient Infrastructure |
As part of the ongoing commitment to network security, this Cisco IOS-XE 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 release 17.18.2, 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 release 26.1.x, 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 Cisco IOS-XE release. Identify and replace all insecure commands with their secure alternatives. • Upgrade behavior: If you upgrade to Cisco IOS-XE release 26.1.x 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 information, refer to Resilient Infrastructure IOS XE Security Warnings Reference |
| Upgrade |
This feature provides a low-latency mechanism for high-priority frames by allowing the suspension of non-critical frames for critical ones. It helps achieve low latency and low jitter for real-time control networks, effectively extending QoS capabilities. When high-priority frames are transmitted, the preempted non-critical frame resumes transmission for multiple splits. |
|
| This feature enables configuring Cisco switches as Media Redundancy Clients (MRC) within an MRP ring, acting as regular ring participants that forwards traffic and continuously monitor link status, reporting any failures to the ring manager (MRM). This approach enhances network resiliency and simplifies deployment, supporting rapid failover and compliance with industrial certification requirements. |
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| This feature allows highly accurate time synchronization between devices, even when MACsec encrypts Ethernet traffic for security. This ensures industrial, utility, or automation networks can maintain precise timing and robust data protection on the same infrastructure. |
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| This feature enables you to interconnect two distinct High-availability Seamless Redundancy (HSR) rings, providing continuous, fault-tolerant communication between them. This capability is crucial in industrial and critical infrastructure environments where zero packet loss and high network availability are paramount. It allows for robust network segmentation and enhanced resilience on IE3505 and IE3505H platforms. |
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| Ease of Use |
Industrial Asset Discovery feature automatically identifies and catalogs directly connected industrial devices without impacting network performance. It also exports inventory data to a syslog server in JSON format, streamlining asset tracking, and security enforcement. |
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| Cisco IE3500 Series Switches support cloud management mode, enabling centralized control through the Meraki dashboard. This functionality supports zero-touch provisioning and cloud-based management for streamlined monitoring and configuration. Additionally, it includes access to a Local Status Page (LSP) to facilitate troubleshooting and setup in environments without DHCP. |
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| Ease of use and ease of setup
|
REP Segment ID Auto-Discovery automates the configuration of Resilient Ethernet Protocol (REP) Segment IDs using CDP. This feature reduces manual effort and prevents mismatches for both standard REP and REP Fast protocols, making it easier to add switches to existing segments or create new daisy-chain segments. |
|
| Upgrade |
This feature enables Cisco Industrial Ethernet (IE) switches to interoperate with existing highly available systems by providing robust controller failover using PROFINET S2 controller redundancy mode. It aims to minimize potential issues and downtime in the event of network or controller failures. |
|
| Software Reliability |
This feature enhances device security and network flexibility by setting Discovery and Configuration Protocol (DCP) operations to read-only mode. It protects the IP address, gateway, and device name from modification. It also helps prevent unexpected connectivity loss by preserving essential network settings. The feature remains compatible with LLDP, SNMP, and CDP, and still allows identification and basic network discovery. |
This section provides a brief description of the new hardware features introduced in Cisco IOS-XE 26.1.x release.
IOS-XE 26.1.1
There are no new hardware features introduced in Cisco IOS-XE 26.1.1 release.
To mitigate potential CRC errors on the Cisco IE3105 platform following a device reload, ensure that auto negotiation settings are consistent across both ends of the link (either enabled or disabled on both sides). We also recommend either replacing the speed auto 100 command with speed 100 duplex full or configuring speed auto 100 at both ends.
Syslog warning on reload for SSH Hostkeys: After a device reload, a syslog warning may appear indicating insufficient key length, even when a strong RSA or EC key is already configured.
Note:
· In the syslog warning message displays crypto key generate rsa modulus <modulus-size> label <label-name>, then 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 warnings:
RSA
Warning Observed: INSECURE DYNAMIC WARNING - Module: SSH.
Command: crypto key generate rsa modulus <modulus-size> label <label-name>.
Reason: An SSH hostkey has been provisioned on the device with insufficient key length.
Remediation: Provision an SSH RSA hostkey with minimum modulus size of 3072 bits for enhanced security.
Sub mode: exec.
Parent CLI: Not Applicable.
EC
Warning Observed: INSECURE DYNAMIC WARNING - Module: SSH.
Command: crypto key generate ec keysize <modulus-size> label <label-name>.
Reason: An SSH hostkey has been provisioned on the device with insufficient key length.
Remediation: Provision an SSH hostkey 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 and associated it using ip ssh ec|rsa <keypair-name>, you can ignore this warning during boot. The configured SSH keypair association is applied after the boot process, and SSH then uses the correct key for secure connections.
Once this configuration is active, SSH uses the correct key for secure connections.
Notice of changes introduced in the Cisco IOS-XE release 17.18.2 and beyond
Cisco is committed to safeguarding our products and customer networks against increasingly sophisticated threat actors. Cisco is improving product security by gradually phasing out legacy and insecure features and protocols. Starting with Cisco IOS XE 17.18.2, the software displays warnings when insecure features, outdated encryption methods, or nonsecure best practices are configured, and recommends more secure alternatives. This change is part of Cisco’s ongoing effort to make products more secure by default while minimizing operational impact.
This list may change over time. The following features and protocols generate warnings in Cisco IOS XE releases after 17.18.1. Refer to the release notes for each release for exact details.
● Plain-text and weak credential storage: Type 0 (plain text), 5 (MD5), or 7 (Vigenère cipher) in configuration files.
Recommendation: Use Type 6 (AES) for reversible credentials, and Type 8 (PBKDF2-SHA-256) or Type 9 (Scrypt) for non-reversible credentials.
● SSHv1
Recommendation: Use SSHv2.
● SNMPv1 and SNMPv2, or SNMPv3 without authentication and encryption
Recommendation: Use SNMPv3 with authentication and encryption (authPriv).
● MD5 (authentication) and 3DES (encryption) in SNMPv3
Recommendation: Use SHA1 or, preferably, SHA2 for authentication, and AES for encryption.
● IP source routing based on IP header options
Recommendation: Do not use this legacy feature.
● TLS 1.0 and TLS 1.1
Recommendation: Use TLS 1.2 or later.
● TLS ciphers using SHA1 for digital signatures
Recommendation: Use ciphers with SHA256 or stronger digital signatures.
● HTTP
Recommendation: Use HTTPS.
● Telnet
Recommendation: Use SSH.
● FTP and TFTP
Recommendation: Use SFTP or HTTPS.
● On-Demand Routing (ODR)
Recommendation: Use a standard routing protocol in place of CDP-based routing information exchange.
● BootP server
Recommendation: Use DHCP or secure boot features such as Secure ZTP.
● TCP and UDP small servers (echo, chargen, discard, daytime)
Recommendation: Do not use these services on network devices.
● IP finger
Recommendation: Do not use this protocol on network devices.
● NTP control messages
Recommendation: Do not use this feature.
● TACACS+ using pre-shared keys and MD5
Recommendation: Use TACACS+ over TLS 1.3, introduced in release Cisco IOS-XE 17.18.1.
Cisco is committed to supporting customers through this transition. Subsequent releases in the Cisco IOS -XE 17.18 train continue to support these features but displays warnings if they are used. Future Cisco IOS-XE release trains may impose additional restrictions on these features which will be communicated through release notes.
The changes introduced in Cisco IOS-XE 17.18 continue to apply in release 26.1.x and later.
This section lists resolved issues in Cisco IOS-XE 26.1.x release.
Note: This software release may contain bug fixes first introduced in other releases. To see additional information, click the bug ID in Cisco Bug Search Tool.
IOS-XE 26.1.1
Table 2. Resolved issues in Cisco IOS-XE 26.1.1 release
| Bug ID |
Description |
| With VPNlLESS login CUIC gadgets failes load. |
This section lists open issues in Cisco IOS-XE 26.1.x release.
Note: This Cisco IOS-XE software release may contain open bugs first identified in other releases. To see additional information, click the bug ID in Cisco Bug Search Tool.
IOS-XE 26.1.1
Table 3. Open issues in Cisco IOS-XE 26.1.1 release
| Bug ID |
Description |
| Serial number printed on physical device does not match the serial number in software |
This section lists known issues in Cisco IOS-XE 26.1.x release.
IOS-XE 26.1.1
There are no known issues in this Cisco IOS-XE 26.1.1 release.
This section lists supported hardware information.
Table 4. Supported IE3500 SKUs
| PID |
Uplink Ports |
Downlink Ports |
||||
| Type |
Ports |
Interface name |
Type |
Ports |
Interface name |
|
| IE-3500-8T3S |
SFP/SFP+ |
3 |
Gigabit Ethernet 1/1-3 |
Copper |
8 |
Gigabit Ethernet 1/4-11 |
| IE-3500-8P3S |
||||||
| IE-3505-8T3S |
||||||
| IE-3505-8P3S |
||||||
| IE-3500-8U3X |
TenGigabit Ethernet 1/1-3 |
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| IE-3500-8T3X |
||||||
Table 5. Supported IE3500H SKUs
| System |
PIDs |
SW |
Uplinks |
Downlinks |
Data Path FPGA |
PoE |
Alternate PIDs (TAA and COO) |
| All Gig Copper |
IE-3500H-8T |
Network Essentials or Network Advantage |
4x1G Copper |
4x1G Copper |
No |
No |
none |
| IE-3500H-16T |
12x1G Copper |
none |
|||||
| IE-3500H-24T |
20x1G Copper |
|
|||||
| Mixed Gig/GE Copper
|
IE-3500H-12FT4T |
12xFE Copper |
No |
No |
none |
||
| IE-3500H-20FT4T |
20xFE Copper |
||||||
| Advanced Copper
|
IE-3505H-16T |
12x1G Copper |
Yes |
No |
none |
||
| POE |
IE-3500H-14P2T |
2x1G Copper |
14x1G Copper |
No |
Yes |
none |
|
| IE-3500H-12P2MU2X |
2x10G SFP |
12x1G POE and 2xMGig UPOE |
Supported expansion modules
Table 6. Supported expansion modules
| PID |
Downlink Ports |
||
| Type |
Ports |
Interface name |
|
| IEM-3500-16P |
Copper RJ45 |
16 PoE |
Gigabit Ethernet 2/1-16 |
| IEM-3500-16T |
16 |
Gigabit Ethernet 2/1-16 |
|
| IEM-3500-8P |
8 PoE |
Gigabit Ethernet 2/1-8 |
|
| IEM-3500-8T |
8 |
Gigabit Ethernet 2/1-8 |
|
| IEM-3500-4MU |
4 PoE |
Gigabit Ethernet 2/1-4 |
|
| IEM-3500-8S |
SFP |
8 |
Gigabit Ethernet 2/1-8 |
| IEM-3500-14T2S |
Copper RJ45/ SFP |
Copper RJ45: 14 SFP: 2 |
Gigabit Ethernet 2/1-16 |
| IEM-3500-6T2S |
Copper RJ45: 6 SFP: 2 |
Gigabit Ethernet 2/1-8 |
|
Web UI system requirements
The WebUI is a web browser-based switch management tool that runs on the switch.
Minimum hardware requirements
Table 7. Minimum hardware requirements
| Processor Speed |
DRAM |
Number of colors |
Resolution |
| 233 MHz minimum 1 GHz recommended |
512 MB 1 GB recommended |
256 |
1280 x 800 or higher |
Operating systems
● Windows 10 or later
● Mac OS X 10.9.5 or later
Browsers
● Google Chrome: Version 59 or later (On Windows and Mac)
● Microsoft Edge
● Mozilla Firefox: Version 54 or later (On Windows and Mac)
● Safari: Version 10 or later (On Mac)
Finding the software version
● The package files for Cisco IOS-XE software can be found on the system board's internal flash memory device (flash:) or an external USB, depending on the platform configuration.
● Use the show version privileged EXEC command to display the software version running on the switch and the model name that is displayed at the end reflects the factory configuration and does not change with software license upgrades.
● Use the dir filesystem: privileged EXEC command to view the names and versions of software image stored in flash memory.
Software images for Cisco IOS-XE 26.1.x
This table provides the file names for the Cisco IOS-XE 26.1.x software images for Cisco IE3500 Series Switches.
Table 8. Software package for Cisco IOS-XE 26.1.x release
| Release |
Image Type |
Platform |
File Name |
| Universal |
IE3500, IE3505, IE3500H and IE3505H |
ie35xx-universalk9.26.01.01.SPA.bin |
Automatic boot loader upgrade
When you upgrade from the existing Cisco IOS-XE release on your switch to a later or newer Cisco IOS-XE release for the first time, the boot loader may be automatically upgraded based on the hardware version of the switch. If a boot loader upgrade occurs, it takes effect on the next reload.
For later Cisco IOS-XE releases, if a new boot loader is included, it may also be automatically upgraded when the new image is booted for the first time.
Caution: Do not power cycle your switch during the upgrade.
Software installation commands
For a successful install, Cisco recommends having free flash space equal to at least twice the image size of flash. If insufficient space is available, remove inactive packages with install remove inactive command or manually delete unnecessary files such as old core files or any other files that occupy a large amount of space in flash.
To install and activate the specified file, and to commit changes to be persistent across reloads, use the install add file filename [ activate commit] command.
Table 9. Summary of software installation commands for install mode
| Command |
Description |
| add file tftp: filename |
Copies the install file package from a remote location to the device and performs a compatibility check for the platform and image versions. |
| activate [auto-abort-timer] |
Activates the file, and reloads the device. The auto-abort-timer keyword automatically rolls back image activation. |
| commit |
Makes changes persistent over reloads. |
| remove |
Deletes all unused and inactive software installation files. |
Table 10. Additional references for Cisco IE3500 Rugged and IE3500 Heavy Duty Series Switches
| Document |
Description |
| Provides information about Cisco IOS-XE. |
|
| Provides warranty information for a specific product or product family. |
|
| Provides information about Cisco IE3500 Rugged Series Switches. |
|
| Provides information about Cisco IE3500 Heavy Duty Series Switches. |
|
| Provides information about Cisco Validated Designs. |
|
| Provides timely and relevant information from Cisco. |
|
| Provides the business outcomes and technical support services needed to maximize the value of your Cisco technologies. |
|
| You can submit a service request here. |
|
| To discover and browse secure, validated enterprise-class apps, products, solutions, and services. |
|
| Provides general networking, training, and certification titles. |
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| You can ask and answer questions, share suggestions, and collaborate with your peers. |
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| Provides most up-to-date, detailed troubleshooting information. Go to Product Support and select your product from the list or enter the name of your product. Look under Troubleshoot and Alerts, to find information for the problem that you are experiencing. |
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