The Practice Round
8:29Coming soon
Eight subnetting questions, fifteen seconds on the clock, no calculator. Every one is a shape the exam actually uses, and every one is solved out loud with the same three steps: count the lit lamps for the prefix, the last lit lamp is the block size, the network is the multiple at or below the host. If the last three lessons taught the method, this is the one that makes it automatic.
You'll learn
- Q1: the network address of 192.168.1.100 with 255.255.255.192 → 192.168.1.64/26
- Q2: the broadcast address of 192.168.1.203/27 → .223
- Q3: which subnet 192.168.1.21/29 is on, and its host range → 192.168.1.16/29, hosts .17–.22
- Q4: how many subnets and hosts when a /24 is subnetted with 255.255.255.240 → 16 subnets of 14
- Q5: at least 50 hosts per subnet, which mask → 255.255.255.192
- Q6: at least six subnets from a /24, which mask → 255.255.255.224
- Q7: which of .128, .191, .150, .192 is a usable host on 192.168.1.128/26 → .150
- Q8: a host whose default gateway is on a different subnet: why it can print but not leave, and the fix
- What the exam calls each thing: network ID, broadcast, usable host range, hosts per subnet, block size, incorrect default gateway
- The real thing: the sixty seconds before question one — the lamp card and the six-row width table on the erasable board
- Exam corner: which default gateway is valid on 192.168.1.64/26
Chapters
- 0:00Eight questions, one clock
- 0:30Questions 1 and 2: which street, which bell tower
- 1:35Questions 3 and 4: the smallest street, how many streets
- 2:59Questions 5 and 6: pick the mask
- 4:14Questions 7 and 8: is it a house, is the gate on the street
- 5:57What the exam calls each thing
- 6:41The real thing: the scratch board
- 7:25Exam corner
- 7:56Recap and next time
Exam objectives: CompTIA Network+ N10-009: 1.7 (IPv4 subnetting), 5.2 (incorrect subnet mask, incorrect default gateway), 5.5 (ipconfig).
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