Support Forum
The Forums are a place to find answers on a range of Fortinet products from peers and product experts.
FransUrbo
New Contributor

DHCP server does not provide IP

I've setup a DHCP server pool to provide 10.0.1/24 and 10.0.4/24 on one of my interfaces. But I can't get an IP on one of my hosts! I see that the requests leaves the host and (something) is received by my Fortigate running "FortiOS v5.6.6 build1630 (GA)" on a "FortiGate 50E" running in NAT mode. But it won't hand out an ip.

 

The config is just a snippet from my real config, not the whole thing. But I've checked and double checked all MAC addresses etc and they are correct. Not sure what more I should include, but ask and I'll provide.

 

 

8 REPLIES 8
Toshi_Esumi
Esteemed Contributor III

The secondary subnets are all on the same broadcast domain with the primary. I wouldn't expect the FGT looks up the second DHCP scope. (I'm waiting somebody says "you're wrong" :)

emnoc
Esteemed Contributor III

I don't believe that's the issue. Is the DHCP-server status enabled? Typically if the DHCP-request comes in and nothing given is a sign the dhcp-server is not enabled.

 

find the pid and  kickstart it and if no pid, than set the status for the dhcp server to "enable"

 

http://socpuppet.blogspot...on-or-any-daemons.html

 

Ken Felix

 

PCNSE 

NSE 

StrongSwan  

PCNSE NSE StrongSwan
ede_pfau
Esteemed Contributor III

I would also suspect that all 4 DHCP servers are seeing the request from the same MAC address and are withholding an offer because of that. You can easily test this by removing 3 of the 4 DHCP servers.

Instead of secondary addresses you could configure VLANs to avoid using the same broadcast domain.


Ede

"Kernel panic: Aiee, killing interrupt handler!"
Ede"Kernel panic: Aiee, killing interrupt handler!"
FransUrbo

Setting up VLANs on Linux is always such a pain! But even if I did that, I "only" need it to do PXE boots, and there's no way to setup VLANs in the firmware of my ancient HP machines.

 

FransUrbo

Was running and HUPping it didn't help...

FransUrbo

What do you mean by "the same broadcast domain with the primary"?

 

But even if I delete all but the 10.0.4/24 server entry, still doesn't work. Same as before - dhclient asks and FGT still receives the request but doesn't respond to it.

 

Dave_Hall
Honored Contributor

@OP Is your test machine connected directly to the fgt or going through a switch?  If through a switch could the switch ports have DHCP snooping enable?

NSE4/FMG-VM64/FortiAnalyzer-VM/6.0 (FWF30E/FW92D/FGT200D/FGT101E/FGT81E)/ FAP220B/221C

NSE4/FMG-VM64/FortiAnalyzer-VM/6.0 (FWF30E/FW92D/FGT200D/FGT101E/FGT81E)/ FAP220B/221C
emnoc
Esteemed Contributor III

One other  items. The use of secondary is bad and just for this reason. With a slight change of the layer3 interfaces and design you could eliminate the big mess with  secondaries.

 

e.g 

config system interface [...] edit "cluster" set vdom "root" set ip 10.0.7.254 255.255.253.0 set allowaccess ping set type hard-switch set scan-botnet-connections block set explicit-web-proxy enable set explicit-ftp-proxy enable set description "OpenStack Cluster" set stp enable set device-identification enable set role lan set snmp-index 6 set secondary-IP enable config secondaryip edit 1 set ip 10.0.1.254 255.255.255.0 set allowaccess ping next end

config system dhcp server edit 1 set mac-acl-default-action block set dns-service local set ntp-service local set domain "openstack.bayour.com" set default-gateway 10.0.8.254 set netmask 255.255.253.0 set interface "cluster" config ip-range edit 1 set start-ip 10.0.4.1 set end-ip 10.0.6.254 next end set timezone-option default set tftp-server "10.0.4.253" set filename "pxelinux"

 

Just my  two cents, but again check that the  dhcp server is  enabled in your config

 

     set status enable iirc

 

Ken Felix

 

PCNSE 

NSE 

StrongSwan  

PCNSE NSE StrongSwan
Labels
Top Kudoed Authors