Cannot Ping PC Directly Connected to Switch – Solving DHCP and Ping Issues

dhcpping

I'm trying to configure a new subnet for my users. DHCP is configured on the switch SW1.

The topology looks like this :
SW1 <===> SW2 <===> PC

There is an etherchannel + trunk link between SW1 and SW2.

For whatever reasons, I cannot ping the PC. It gets an IP just fine.

Here is my configuration on SW1:

ip dhcp class rangeuser
ip dhcp pool UsersLAN
network 10.239.146.0 255.255.255.0
domain-anme xx.com
dns-server 172.30.184.5 172.30.184.4
default-router 10.239.146.1
lease 0 2
class rangeuser
 address range 10.239.146.10 10.239.146.250
  address 10.239.146.82 client-id 0114.b31f.17c5.a7

int po24
switchport mode trunk

int vlan11
 ip address 10.239.146.5 255.255.255.0

And on SW2:

 int po24
  switchport mode trunk

 int gi2/0/41
  switchport access vlan 11
  switchport mode access
  switchport voice vlan 30
  spanning-tree portfast
  spanning-tree bpduguard enable

Show ip dhcp binding displays the lease. But when I try to ping using source interface vlan 11, it simply does not work. If I put back the access port into the old user vlan (vlan 10), then I can ping just fine with my switch.

What's going on here ?

Best Answer

I figured it out eventually.

When a computer has joined a domain, it tries to contact its domain controller after getting an IP. In Vlan 10, it was able to do so successfully, and would categorize the network as a "Domain network". The Windows Firewall was disabled for domain networks.

When in Vlan11, the subnet was not allowed to contact the domain controller because it was dropped on a Firewall along the way. This resulted in the network being categorized as a "Public network", where the Windows firewall was enabled.

After opening the network flows, it started working.

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