I86bi-linux-l3-adventerprisek9-ms.155-2.t.bin Here

show version
show license feature
show ip route
show crypto isakmp sa
show ip ospf neighbor
show running-config

Expected output snippet from show version:

IOS (tm) Linux Software (I86BI_LINUX-L3-ADVENTERPRISEK9-M), Version 15.5(2)T
ROM: IOS-on-Unix Bootstrap Program
R1 uptime is 10 minutes
System returned to ROM by reload at 0
System image file is "unix:I86bi-linux-l3-adventerprisek9-ms.155-2.t.bin"
cisco I86BI (IW-M) processor (revision 0) with 458752K/65536K bytes of memory.

To understand why this image is so popular, we must first decode its filename. Cisco naming conventions are dense, but they tell us exactly what we are working with: I86bi-linux-l3-adventerprisek9-ms.155-2.t.bin

ms: This stands for "Master" or "Mainline" release integrated with specific feature sets. It often implies a stable convergence of features.

155-2.t: This is the version number. It corresponds to IOS Version 15.5(2)T. This is a "Train" release (T), meaning it introduces new features compared to the standard maintenance releases (M).

.bin: The standard binary executable extension.

The 15.5(2)T version is widely used for CCIE Routing & Switching v5 (now legacy) and CCNA/CCNP studies. Many workbook topologies (e.g., INE, Narbik) reference this image. show version show license feature show ip route

conf t
hostname SW1
ip routing
vlan 10,20
int vlan 10
 ip address 192.168.10.1 255.255.255.0
 no shut
int vlan 20
 ip address 192.168.20.1 255.255.255.0
 no shut
router ospf 1
 network 192.168.10.0 0.0.0.255 area 0
 network 192.168.20.0 0.0.0.255 area 0