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Networking
Ethernet Articles
IPv4 Articles
IPv6 Articles
Routing Articles
OSPF Articles
- What Is OSPF
- OSPF Router ID
- OSPF Packet Types and Header Format
- OSPF Authentication
- OSPF Neighbor States
- OSPF Options Field
- OSPF DR and BDR
- OSPF Network Types
- OSPF Cost (Metric)
- OSPF External Routes (Redistributing Static Routes)
- OSPF Multiple Areas and the ABR
- OSPF Virtual Links
- OSPF Stub and Totally Stubby Areas
- OSPF NSSA and Totally NSSA
- OSPF Default Route
- OSPF Route Summarization
- OSPF LSAs and the LSA Header
- OSPF Convergence Timers (SPF / LSA Throttling)
- OSPF router-LSA (type 1)
- OSPF network-LSA (type 2)
- OSPF summary-LSA (type 3)
- OSPF ASBR summary-LSA (type 4)
- OSPF AS external-LSA (type 5)
- OSPF NSSA External-LSA (Type 7)
IS-IS Articles
- What Is IS-IS
- IS-IS NSAP Addresses and the NET (System ID)
- IS-IS Level 1 and Level 2 (the hierarchy)
- IS-IS Packet Types and Header Format
- IS-IS Adjacency Formation and States
- IS-IS DIS and the Pseudonode
- IS-IS Network Types (broadcast / point-to-point)
- IS-IS Metrics (narrow and wide)
- IS-IS Authentication (hello-password and lsp-password)
- IS-IS LSPs and the Link-State Database
- The Main IS-IS TLVs
- IS-IS Flooding and LSDB Synchronisation
- IS-IS SPF Computation and Route Selection
- The IS-IS ATT Bit and the Level 1 Default Route
- IS-IS Route Leaking and the Up/Down Bit
- IS-IS Route Summarization
- The IS-IS Overload Bit
- IS-IS Hello and Holding Time
- IS-IS Convergence Timers (SPF / LSP Generation)
- IS-IS Redistribution (connected / static)
- IS-IS Redistribution of BGP Routes
BGP Articles
- BGP (Border Gateway Protocol)
- BGP Messages
- BGP Neighbor States
- iBGP and eBGP
- BGP next-hop-self
- BGP Route Reflector
- BGP Path Attributes and Best Path Selection
- BGP ORIGIN Attribute
- BGP AS_PATH Attribute
- BGP NEXT_HOP Attribute
- BGP LOCAL_PREF Attribute
- BGP MED Attribute
- BGP WEIGHT Attribute
- BGP COMMUNITY Attribute
- BGP Route Aggregation (aggregate-address)
- MP-BGP (Multiprotocol Extensions)
- BGP Extended Community
- BGP Multipath (maximum-paths)
- BGP Four-Octet AS Numbers (RFC 6793)
- Removing Private AS Numbers in BGP (remove-private-AS)
- BGP ADD-PATH (RFC 7911)
- BGP PIC (Prefix Independent Convergence)
MPLS Articles
- What Is MPLS
- MPLS Labels and the Label Stack
- MPLS Label Operations (push / swap / pop) and PHP
- MPLS TTL Processing and MTU
- What Is LDP
- LDP Label Distribution Modes and Label Spaces
- LDP-IGP Synchronization and LDP Session Protection
- LDP Label Advertisement Control (Filtering)
- LDP Session Authentication (TCP MD5)
- MPLS OAM (LSP Ping and LSP Traceroute)
- What Is MPLS TE (RSVP-TE)
- MPLS TE CSPF and Path Constraints (Bandwidth, Affinity, TE Metric)
- Steering Traffic into MPLS TE Tunnels
- MPLS TE Fast Reroute (Link and Node Protection)
- MPLS TE Fast Reroute (Auto-Tunnel Backup and SRLG)
- MPLS QoS (Traffic Class and Uniform / Pipe / Short-Pipe)
- MPLS QoS Rate Control and Queuing (policer / shaper / priority)
Network Devices
Cisco IOS XE Articles
IOS XE Operation Methods
IOS XE Basic Configuration
Cisco IOS XR Articles
IOS XR Operation Methods
IOS XR Basic Configuration
- IOS XR Hostname Configuration (hostname)
- IOS XR Interface Configuration (shutdown/no shutdown) and Verification
- Configuring an IPv4 Address on a Cisco IOS XR Interface
- Configuring an IPv4 Static Route on Cisco IOS XR
- IOS XR OSPF Basic Configuration
- IOS XR OSPF DR/BDR Priority Configuration
- IOS XR OSPF Stub Area Configuration (stub / totally stub)
- IOS XR OSPF Network Type Configuration
Linux
Ubuntu26.04 Articles
Ubuntu 26.04 Configuration
- Changing the Hostname on Ubuntu 26.04 LTS Server (hostnamectl)
- Updating Packages on Ubuntu 26.04 LTS Server (apt update / upgrade)
- Setting the Timezone and Time Synchronisation on Ubuntu 26.04 LTS Server
- Creating Users and Granting sudo Privileges on Ubuntu 26.04 LTS Server
- Configuring the SSH Server on Ubuntu 26.04 LTS Server
- Setting Up a telnet Server on Ubuntu 26.04 LTS Server
- Configuring inetd (the Super-Server) on Ubuntu 26.04 LTS Server
- Setting Up a TFTP Server on Ubuntu 26.04 LTS Server (tftpd-hpa)
- FTP Server Setup on Ubuntu 26.04 LTS Server (vsftpd)
- Setting Up a syslog Server on Ubuntu 26.04 LTS Server (rsyslog)
- Managing Services with systemctl and Reading Logs with journalctl on Ubuntu 26.04 LTS Server
- Configuring Automatic Updates on Ubuntu 26.04 LTS Server (unattended-upgrades)
- Automating the Initial Setup of Ubuntu 26.04 LTS Server with cloud-init
- Configuring Kernel Parameters on Ubuntu 26.04 LTS Server (sysctl)
- Configuring the Network on Ubuntu 26.04 LTS Server (Netplan)
- Configuring Name Resolution on Ubuntu 26.04 LTS Server (systemd-resolved)
- Changing the NTP Source on Ubuntu 26.04 LTS Server (chrony)
- Static Routes on Ubuntu 26.04 LTS Server (Netplan)
- How to Install the Latest neovim from the Official Site on Ubuntu 26.04 LTS Server