Part 2 of the BGP series for CCNP ENCOR 350-401 v1.2: TCP 179, the six-state finite state machine, the five message types, timer negotiation, eBGP multihop versus TTL security, MD5 authentication, and a four-layer troubleshooting method with four hands-on labs.
Part 1 of a four-part BGP series for CCNP ENCOR 350-401 v1.2: why BGP is a policy protocol rather than a metric protocol, autonomous systems and ASN ranges, the rules that separate eBGP from iBGP, the iBGP full-mesh and next-hop problems, BGP's three tables, and four hands-on labs with answers.
Full password recovery procedure for a Cisco Catalyst 9200 running IOS-XE, using the ROMMON SWITCH_IGNORE_STARTUP_CFG variable — with console captures, the correct command order, how to clear the ignore flag, and the pitfalls that leave a switch booting with no configuration.
A full walk through Quality of Service for CCNP ENCOR 350-401 v1.2 topic 1.4: the four impairments, DiffServ marking and PHBs, the six QoS components, MQC policy design, Catalyst switch implementation, worked bandwidth and token-bucket maths, and five hands-on labs with answers.
The finale: a safe bulk config-push tool that previews a per-device diff, gates the commit behind confirmation, and reports what changed — plus where to take Python next.
A complete config-backup tool: read a YAML inventory, pull running-configs with Netmiko, save to disk, and commit to Git so every change becomes a reviewable diff.
Turn show command output into lists of dicts with TextFSM and ntc-templates — parse_output for common commands, hand-written templates for the rest, no regex per command.
An introduction to NETCONF from Python with ncclient — datastores, capabilities, get-config filters, edit-config, and the candidate/commit transactional workflow on IOS-XE.
Drive network controllers with Python's requests library — HTTP verbs, status codes, token auth, JSON bodies, and the token-then-query pattern used by DNA Center and Meraki.
Use Jinja2 to turn a YAML inventory into finished device configs — expressions, loops, conditionals, file-based templates, and filters, the same engine Ansible uses.