Hello
I have a 3750 swtich where I configured 2 vlans : 610 & 611.
On the interface Gi1/0/23, I configured this interface in trunk mode for 610&611. This physical interface is connected to my firewall on interface eth5. On my firewall, I configured 2 sub-interface (one for each vlan) : 10.251.100.1/26 for vlan 610 and 10.251.100.65/27 for vlan 611.
On my C3750 switch, I have the following configuraiton :
interface GigabitEthernet1/0/23
description Firewall_eth5
switchport trunk allowed vlan 610,611
switchport trunk encapsulation dot1q
switchport mode trunk
switchport nonegotiate
logging event trunk-status
logging event bundle-status
priority-queue out
!
interface Vlan610
ip address 10.251.100.4 255.255.255.192
ip helper-address 10.251.50.12
no ip redirects
no ip proxy-arp
no ip route-cache
!
interface Vlan611
no ip address
ip helper-address 10.251.50.12
no ip route-cache
!
ip default-gateway 10.251.100.1
!
Remotly, I can connected on my swtich on ip 10.251.100.4.
On computer connected on vlan 610, no problem, they can boot and they find my DHCP server (10.251.50.12). But in vlan 611, the boot failed because the computer can't contact my DHCP server (10.251.50.12). But, if configured a laptop connected on vlan 611 with an static IP (10.251.100.70/255.255.255.224 and gateway 10.251.100.65), the computer is reachable.
Why I can't contact my DHCP server ? I checked the firewall but there is no dhcp trafic from the vlan 611...
BR
