Kerry CorderoKISS IT Design Principle - Human Error Prevention
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Kerry Cordero
JoinedMay 2, 2023
Articles667
20+ years of experience and proven performance in large scale enterprise network infrastructure architecture, design, implementation, migration, security, operation, troubleshooting, leading/managing teams, and budgets. I have a BS in Cybersecurity and a Master's from the University of Florida.
Routing & Switching

Cisco uRPF

Let’s first talk about what happens when a router receives a unicast IP Packet. In order for the router to...
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Security

Palo Alto Application Dependency

When configuring App-ID in Palo Alto Networks firewalls, it is crucial to pay attention to the “Depends on:” section in...
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Security

Okta Voice Call Authentication MFA Being Blocked – Tmobile Spam Blocking

I noticed that the Okta Voice Call Authentication callback option for MFA was not working for my Cell phone number....
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Security

Palo Alto – GlobalProtect Gateway Selection Priority Process Algorithm

When setting up your system, it’s crucial to understand how this algorithm operates. It utilizes priority and response time to...
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Data CenterLaptops & DesktopsRouting & SwitchingSecurityServersWireless

SNMP Polling vs Traps

The difference between these is who is initiating the conversation. In Polling, the monitoring server is initiating the conversation asking...
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Data CenterLaptops & DesktopsRouting & SwitchingServers

DNS Rewrite aka DNS Doctoring

DNS rewrite or DNS Doctoring has been around on the Cisco ASA’s for a while. Palo Alto firewalls received this...
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CloudCodeData CenterLaptops & DesktopsLoad BalancingRouting & SwitchingSecurityServersVOIPWireless

Common Ports

Cloud

AWS Public IP vs Elastic IP

The key difference is the Elastic IP does NOT change if you terminate or restart an instance. Think of it...
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Laptops & DesktopsServers

10 Common Reasons for a Windows AD Lockout

1. Programs with cached credentials 2. Changed password in a service account 3. Having a bad password limit that’s too...
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Routing & Switching

IPv4 CIDR Blocks

  Network Bits Subnet Mask Number of Subnets Number of Hosts /8 255.0.0.0 0 16777214 /9 255.128.0.0 2 (0) 8388606...
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  • Home
  • About
  • Disclaimer
  • Guides and Slides
    • AWS Well-Architected Framework
    • Facebook – Running BGP in the Data Center at Scale
    • Microsoft – Experiences with BGP in Large Scale Data Centers
    • Palo Alto PCNSE Study Guide
  • IP Calculator
  • Links
  • Contact

Categories

  • AI
  • Business Management
  • Cloud
  • Code
  • Data Center
  • Laptops & Desktops
  • Load Balancing
  • Routing & Switching
  • Security
  • Servers
  • Uncategorized
  • VOIP
  • Wireless

Tags

Active Directory (AD) AWS Azure Best Practices BGP Certificates Cisco Cisco ACI Cisco ASA Cisco ASR Cisco Catalyst Cisco CLI Cisco ISE Cisco Nexus Cisco Stack DDOS Design DNS EIGRP F5 HTTP(S) IP Addressing and Subnetting Microsoft IIS Microsoft SQL Microsoft Windows Okta OSPF Packet Capture Palo Alto Palo Alto CLI PDF Planning Ports PowerShell python QOS snmp Splunk SSL Structured Cabling TLS Troubleshooting Upgrade VMWare Zscaler
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