Using the files ive given make an ACL in the far r...

Created on: November 4, 2025

Answered using GPT-5 Thinking by Chat01

Question

AMX-ISP-Core-FIN-v6.0.pkt
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Using the files ive given make an ACL in the far right with serial connections

Thought

Clarifying ACL configuration

I'm trying to understand a Cisco ACL configuration. The "permit tcp any host" command seems to allow traffic to a specific destination IP, while terms like "established" or "range" specify connection types. I'm not entirely sure about the destination or source ports, especially whether they refer to server or client. There's also the issue of whether inbound traffic is allowed for the corporate network.

Implementing ACL on ISP router

It seems like the user wants an ACL applied to the far-right router, which is likely on the ISP side based on the Packet Tracer topology. The ACL should permit inbound ports 80, 443, and 53, and allow ICMP between the corp router and the ISP router. Some specific IPs (like 200.200.0.36 for DNS) are involved here.

Creating the ACL configuration

I’ll create an ACL named "CORP_FW_IN" for inbound traffic on the s0/1/0 interface, controlling access for both A3.com and NATEX.com networks. The instructions suggest combining ACL entries for both networks. I’ll provide the necessary commands along with explanations. Finally, I’ll prepare it for download as "acl_config.txt."

Proposing the ACL configuration

I'll propose creating the extended ACL "CORP_FW_IN" with the following rules:

  • Permit inbound HTTP/HTTPS traffic to the A3.com (200.200.9.243) and NATEX.com (200.200.9.250) servers on ports 80 and 443.
  • Allow inbound DNS responses from ISP DNS (200.200.0.36) to specified web server hosts, ensuring the DNS reply targets ephemeral ports greater than 1024.

Configuring ACL for NATEX network

I'll configure an extended ACL for NATEX network with the following:

  • Allow inbound HTTP/HTTPS traffic to NATEX.com server.
  • Permit DNS responses from ISP DNS to NATEX server’s IP.
  • Allow pings between corp router (200.200.9.229) and ISP router (200.200.9.230).

I'll include basic commands in the correct Cisco ACL syntax and provide appropriate instructions for applying them to the "far-right" router.

Thought for 2m 2s

Answer

Got it! Here’s a ready-to-paste ACL for the far-right router with the serial links. It matches the screenshot you shared (HTTP/HTTPS to the public web servers, DNS replies from 200.200.0.36, and ICMP between the p2p serial IPs), then denies everything else and logs.

What it allows

  • Public access to the A3.com web server 200.200.9.243 on 80/443
  • Public access to the NATEX.com web server 200.200.9.250 on 80/443
  • NATEX inside host 200.200.9.251 can browse out to the Internet on 80/443
  • DNS replies from ISP DNS 200.200.0.36 back to 200.200.9.243 and 200.200.9.251 (source port 53 → dest ephemeral)
  • ICMP echo/echo-reply between 200.200.9.229 (corp) and 200.200.9.230 (ISP) on the p2p serial

Where to apply

  • Apply inbound on the customer-facing serial interface(s), e.g. s0/1/0 (and s0/1/1 if you have a second customer link).
  • In Packet Tracer: open the far-right router, go to CLI: enableconf t, then paste these lines.

Config (paste this)

text
conf t ip access-list extended CORP_FW_IN remark === Public web servers reachable from the Internet === remark A3.com web server permit tcp any host 200.200.9.243 eq 80 permit tcp any host 200.200.9.243 eq 443 remark NATEX.com web server permit tcp any host 200.200.9.250 eq 80 permit tcp any host 200.200.9.250 eq 443 remark === Inside host allowed to browse the Internet === remark NATEX client can browse web permit tcp host 200.200.9.251 any eq 80 permit tcp host 200.200.9.251 any eq 443 remark === DNS replies from ISP DNS (200.200.0.36) to inside hosts/servers === permit udp host 200.200.0.36 eq 53 host 200.200.9.243 gt 1023 permit udp host 200.200.0.36 eq 53 host 200.200.9.251 gt 1023 remark === P2P serial ping between Corp (.229) and ISP (.230) === permit icmp host 200.200.9.229 host 200.200.9.230 echo permit icmp host 200.200.9.230 host 200.200.9.229 echo-reply remark === Default deny with logging === deny ip any any log exit interface s0/1/0 ip access-group CORP_FW_IN in ! If you have a second customer serial, uncomment and apply here too: ! interface s0/1/1 ! ip access-group CORP_FW_IN in end wr mem

I also saved this as a tiny text file so you can copy/paste straight into the router CLI:
Download the ACL config

If your serial interface name differs, run show ip interface brief on the far-right router and apply the ACL on the correct Serial x/x/x in the inbound direction.

Question

[Class Name]-[first 3 consonant of surname]-[initial of first name]-[R for router / SW for switch]-[sequence number 3 digits]

Using the given format, use my name "Andrei R. Calarion"

Thought

Applying naming convention to Andrei's request

The user asked for a name based on a specific format, using their name "Andrei R. Calarion." I'll follow the format and fill in placeholders where necessary. For example, using "CLASSNAME" for the class and "R" for router (since they didn't specify). The result could look something like:

"CLASSNAME-CAL-R-001" or "CLASSNAME-CAL-R-002".

Generating name examples based on provided format

The user's surname is "Calarion," so the first three consonants are C, L, and R. The initial of the first name is "A" (no need for the middle initial). For the class name, I’ll use placeholders like "CLASS" or something relevant like "Net101."

An example might be: "CCNA2-CLR-A-R-001"

Thought for 14s

Answer

Here you go—based on Andrei R. Calarion:

  • First 3 consonants of surname (Calarion): CLR
  • First name initial (Andrei): A

Plugged into your format:

  • [ClassName]-CLR-A-R-001 ← for a router
  • [ClassName]-CLR-A-SW-001 ← for a switch

(Replace [ClassName] with your actual class, e.g., CCNA2-CLR-A-R-001.)

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