Lab – Bridge Troll
Verify RTR4 has reachability to RTR1’s Loopback. Log into RTR4 and advertise its loopback into OSPF. The password is the smallest MTU configured along the path.
Uploaded: July 14, 2026

SHA-256: 0c535d6013435fc216f68e9fd6748ee9413c28e39a20efb32d5a1254f9b83686
Download is zip containing YAML lab file
CML Free (IOL)
SHA-256: 268f75bb9e23ca37e6b8bfa760457f33366ccdbb893d1b1cb85252f302f0008a
Download is zip containing YAML lab file.
SHA-256: 67fc22ecc5bbdc287d0500a10be48fa9245ec28114016ab9eb9bbea2e0f798f9
Download is a zip containing UNL lab file
SHA-256:
Download is zip containing portable lab file
- To verify RTR4 has connectivity to RTR1’s loopback issue the command ping 34.1.1.4 source lo0 on RTR1. This will activate a script that allows you to SSH into RTR4.
- To get the mtu, issue the command ping 34.1.1.4 size {size} df-bit. Repeat until your find a value the smallest value that works.
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