VLSM and DHCP

jmorris92jmorris92 Member Posts: 24 ■□□□□□□□□□
in CCNA & CCENT
Hi everyone, i'm working on a lab with custom IP addressing for VLANS of different sized hosts and it seems to work for the most part:
VLAN12 1950hosts 172.16.8.0
VLAN11 1850hosts 172.16.16.0
VLAN21 1650hosts 172.16.24.0
VLAN22 1550hosts 172.16.32.0
VLAN31 850hosts 172.16.40.0
VLAN32 750hosts 172.16.44.0
172.16.51.0 /30 and 172.16.52.0 /30 for router interconnections, 172.16.1.1 for gateway and 172.16.2.1 for gateway for the two seperate sections of the network.
Most of this lab is working I can ping across the whole network between PC's and DHCP and interVLAN routing works except for one PC on VLAN32 which should have an IP of 172.16.44.5+, instead it gets an IP of 172.16.40.2? Which is in the VLAN31 range rather than VLAN32. It can ping to some other pc's on its section of the network but not all across the way. I've double checked the VLAN config for 32 and the dhcp pool vlan32 and they are using the correct network .44.0, so i'm a bit confused.
Here's a .pkt for it if anyone could possibly look and tell me what i'm doing wrong it'd be greatly appreciated: https://www.dropbox.com/s/xja75fy6hhjyo1v/lan%2001%20mostly%20working.pkt
Gonna work on some NAT today and ACLs for this network.

Thanks :)
Edit: I realised i'd stupidly put PC in vlan32 on wrong port, changed it to the right but no avail icon_sad.gif
· Share on FacebookShare on Twitter

Comments

  • Jon_CiscoJon_Cisco Member Posts: 1,772 ■■■■■■■■□□
    take a look at the show runs for vlan 31 and 32 pools
    · Share on FacebookShare on Twitter
  • jmorris92jmorris92 Member Posts: 24 ■□□□□□□□□□
    Ah brilliant, I swear I changed that and it didn't take effect. I'm gonna 'no ip dhcp pool' it and redo them. Thanks!
    I swear a lot of problems are often such simple, stupid things lol

    icon_cheers.gif
    · Share on FacebookShare on Twitter
  • jmorris92jmorris92 Member Posts: 24 ■□□□□□□□□□
    Okay I was putting in 255.255.255.248 as it's subnetmask and I believ it should be 255.255.255.252 as it's a smaller block size. That sorted it out on the show run prompt
    ip dhcp pool vlan12
    network 172.16.8.0 255.255.248.0
    default-router 172.16.2.1
    ip dhcp pool vlan22
    network 172.16.32.0 255.255.248.0
    default-router 172.16.2.1
    ip dhcp pool vlan32
    network 172.16.44.0 255.255.252.0
    default-router 172.16.2.1
    But when I go to request IP, it gives me the infamous DHCP request failed - any ideas?
    · Share on FacebookShare on Twitter
  • jmorris92jmorris92 Member Posts: 24 ■□□□□□□□□□
    Sorted it thanks, it was all to do with subnet masks on VLANs and subinterfaces - whether they were /21, /22. Brilliant, i'm starting an internship soon at a big processor designer company and hopefully i'll be able to take my CCNA. I've done CCNA1-4 through Netacad at uni and got 80%+ so do you think I'm ready to take ICND1 atleast?

    Thanks!
    · Share on FacebookShare on Twitter
  • Jon_CiscoJon_Cisco Member Posts: 1,772 ■■■■■■■■□□
    Nice work. I'm hoping to take ICND1 soon. I think you are probably a little ahead of me and it looks like you should be good to take the test.

    Here is a great site for practicing subnetting quickly. Subnetting Practice Questions
    I appreciate you posting the packet tracers as it helps everyone with a little troubleshooting.

    Good Luck
    · Share on FacebookShare on Twitter
  • jmorris92jmorris92 Member Posts: 24 ■□□□□□□□□□
    Ah good luck with it! Thanks that site looks pretty good i'll be sure to check it out as my subnetting is a bit off
    · Share on FacebookShare on Twitter
Sign In or Register to comment.