Today's stumbling blocks in my memory

These are just a few points I want to reconsider today.  It is best to be clear and particular about them.

One practice exam question I was incorrect in answering was the "host mask" vs. "inverse host mask."  I had incorrectly marked the answer for a host mask in an ACL as 255.255.255.255.  The reality is that a host mask in an ACL is 0.0.0.0 -which means that all bits must match.

From the Cisco website, I summarize:

In an inverse mask, a 0 must be an exact match to be considered for the traffic routing, and a 1 is a "don't care."  ACL equivalents:

• The source/source-wildcard of 0.0.0.0/255.255.255.255 means "any". (although the source could be any IP address whatsoever - all will still apply)
• The source/wildcard of 10.1.1.2/0.0.0.0 is the same as "host 10.1.1.2".  

DHCP configuration cheat-sheet

1. prepare your excluded addresses
2. Create your pool
3. Add the network
4. Add the domain name
5. Add the default router
6. Add the DNS servers

As an example:
R1(config)#ip dhcp excluded-address 10.1.1.1
R1(config)#ip dhcp pool MYPOOL
R1(dhcp-config)#network 10.1.1.0 /24
R1(dhcp-config)#domain-name madhouse.local
R1(dhcp-config)#default-router 10.1.1.1
R1(dhcp-config)#dns-server 8.8.8.8 8.8.4.4

Dynamic NAT

I configured a dynamic NAT lab tonight, also.  One of the things I wanted to remind myself was that the NAT statement when configuring dynamic NAT does not require the overload keyword, as this is doing IP-to-IP translation and not port translation (or PAT).

I also looked up what exactly a RIP flash update is.  A flash update is an update that is sent to neighbor routers when a route change takes place.  This occurs in both RIPv1 and RIPv2 - however that is a "triggered update" which is a characteristic of Link-State routing protocols, not distance-vector.  This leaves grey area in my understanding of RIP, but at least I understand it now.