Cisco Read-Only User: Privilege Levels vs Parser Views
Built in my home lab on IOS XE 17.18: a privilege 5 NOC user got an empty config, then every secret. Parser views worked, once exec and console authorization were on.
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All VTY Lines Busy on Cisco IOS XE: Fix Stale SSH Sessions
Built in my home lab on IOS XE 17.18: stale SSH sessions filled every VTY line and locked the admin out. Keepalives, exec-timeout and a reserved line fixed it.
Cisco Password Types 7, 5, 8, 9: Audit and Migrate on IOS XE
Built in my home lab on IOS XE 17.18: decoded every Type 7 password in seconds, migrated to Type 8, and broke Type 6 by removing the master key.
login block-for Locked Out the NOC: quiet-mode access-class
Built in my home lab on IOS XE 17.18: login block-for quiet mode locked out the admin too. A quiet-mode access-class let the NOC in while the attacker stayed refused.
SNMP RW Community Abuse on IOS XE: snmpset, Then SNMPv3 Fix
Built in my home lab on IOS XE 17.18: a sniffed SNMPv2c RW community renamed the router and shut OSPF. SNMPv3 authPriv with an ACL stopped it.
CoPP Dropping OSPF Hellos: Neighbor Down in class-default
Built in my home lab on IOS XE 17.18: a strict CoPP policy policed OSPF together with an ICMP flood, the neighbor went down, and one routing class fixed it.
VTY Access-Class Lockout on IOS XE: SSH and Management VRF
Built in my home lab on IOS XE 17.18: a wrong VTY access-class locked out SSH, then a management VRF did it again with no ACL hits. Both recovered from the console.
Containerlab Packet Capture: Save show Output and a pcap
Built in my home lab: one script pulls show output from an IOL console, captures a ping in the client's network namespace, redacts management IPs, then cleans up.
FMC Home Lab RAM: What Ran Beside a 32 GB FMCv on One Host
Built in my home lab: FMCv held 32 GiB of a 63 GiB host. IOL, IOSv-L2, ASAv and one-FTDv labs ran beside it; a dual-FTDv boot left FMC unhealthy for 183 s.
IOL vs IOSv in Containerlab: Which Image Passed Each Lab Test
Built in my home lab: twelve Containerlab tests decide IOL, IOL-L2 or IOSv-L2. IOSv-L2 won dynamic DHCP snooping and 802.1X; IOL-L2 won IPSG, RA Guard and SPAN.
Syslog Timestamps Out of Order: ASA Timezone vs IOS XE Logs
Built in my home lab: one ICMP packet, an IOS XE permit and an ASA deny. A legacy ASA timestamp with no timezone flipped the order; UTC and rfc5424 fixed it.
Zeek Rogue DHCP and ARP Spoofing Detection: Why SPAN Matters
Built in my home lab: a 51-line Zeek script flags rogue DHCP and gateway ARP spoofing, but only after SPAN sends it the unicast attack frames.