While 155-2.T is robust, it is not without quirks that lab engineers must know:

Example startup config snippet:

The 15.5(2)T release is categorized as an "Extended Maintenance Release" (EMR). Unlike standard T-trains which reach End-of-Support (EoS) quickly,

: Defaults to 8 Ethernet and 8 Serial interfaces.

: As a 32-bit binary, it may not execute natively on newer ARM-based systems (like Apple M1/M2) without specific emulation like QEMU User Emulation Common Use Cases Certification Prep

Because this image uses the feature set, it is frequently used by candidates preparing for CCNP and CCIE certifications. Key capabilities include: