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ARP Caching and Timeout

From time to time I find myself craving to the fundamentals; I do this for two main reasons, the first one is that fundamentals are the building blocks of all complex networking topics and deeply understanding them makes a better engineer, the second one is longing to simplicity after doing some complex tasks. One of these fundamentals that is worth reviewing is the Address Resolution Protocol, this protocol is one of the main building blocks of any network existing on earth today.

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How-to: Avoid DNS lookup when mistyping a command

If domain lookup is enabled (default) the router treats each mistyped command as a hostname and tries to resolve its IP address by querying the DNS server. This behavior is undesirable in most cases because it wastes network administrators time waiting for routers trying to resolve mistyped commands. R2#xyz Translating "xyz"...domain server ( Translating "xyz"...domain server ( ( Translating "xyz"...domain server ( % Unknown command or computer name, or unable to find computer address This waste of time can be avoided with one of the following solutions: Solution1:Disabling domain lookup: This solutions is suitable to LAB environments when your routers …

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How-TO: Configure DHCP on a CISCO router

This post is about configuring a CISCO router to act as a DHCP server in your network. Task1: Configure R1 to act as a DHCP server and provide all network information to hosts in the LAN dynamically. (R1 and R2 are directly connected via Ethernet) Server Configuration (R1) !– enable dhcp server (default) service dhcp ! — defining DHCP pool with all network information ip dhcp pool OFFICE network domain-name networkers-online.com default-router !– gateway address dns-server !– DNS servers netbios-name-server !– WINS servers lease 2 !– lease time !– defining static binding to R2 …

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