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FB
New Contributor

Unable to get IP from my own MS DHCP Server when using SSID in TUNNEL MODE and VLANs

Unable to get IP from my own MS DHCP Server when using SSID in TUNNEL MODE and VLANs

 

The scenario:

 

FortiAP 231F  6.4.7  on VLAN 700

Fortigate 6.4.7 controller on VLAN 700

MS DHCP Server on VLAN500 and several scopes, for several SSIDs, 300, 301, 400, etc (tested Win2012R2 or Win2019)

3COM Switch 2620 VLAN500 untagged and tagged VLANs 300, 301 and 400 for the AP ports

Work Ok on BRIDGE MODE

 

We currently have a RUCKUS solution, workking perfectly, flawslessly, for more than 5 years and we´re planning to replace Ruckus, using FortiAp231F.  MS DHCP working fine, no problems at all

 

What´s happening: 1) Based on packet capture, we can see the DISCOVER, asking for IP, we can see an OFFER and nothing more

2) dhcprelay debug 255 is showing:

 

(xid:d0c789d1) got a DHCPDISCOVER (xid:d0c789d1) Warning! can't get server id from client message Insert option(82), len(12) found route to 10.121.60.4 via 10.121.62.250 iif=59 oif=12/port4, mode=auto, ifname= (xid:d0c789d1) forwarding dhcp request from 10.121.62.2:67 to 10.121.60.4:67 (xid:d0c789d1) L2 socket: received request message from 0.0.0.0:68 to 255.255.255.255 at CNS-MOBILE (xid:d0c789d1) got a DHCPDISCOVER (xid:d0c789d1) Warning! can't get server id from client message Insert option(82), len(12) found route to 10.121.60.4 via 10.121.62.250 iif=59 oif=12/port4, mode=auto, ifname= (xid:d0c789d1) forwarding dhcp request from 10.121.62.2:67 to 10.121.60.4:67

 

We already tried to enable the option-82 informations on SSID, sending more info to DHCP, , no luck

 

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4 REPLIES 4
rwpatterson
Valued Contributor III

You need to add a DHCP relay on the Fortigate for the VLANs that have remote DHCP servers. The below is on version 5.2.13 (build 0762).

Bob - self proclaimed posting junkie!
See my Fortigate related scripts at: http://fortigate.camerabob.com

Bob - self proclaimed posting junkie!See my Fortigate related scripts at: http://fortigate.camerabob.com
FB
New Contributor

Is done already, Fortinet support is algo looking at the issue

 

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FB
New Contributor

set dhcp-relay-service enable set dhcp-relay-ip "10.121.60.4"

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FB
New Contributor

FULL OFFER reply from DHCP

 

Frame: Number = 476, Captured Frame Length = 360, MediaType = ETHERNET + Ethernet: Etype = Internet IP (IPv4),DestinationAddress:[B8-AF-67-05-DD-B7],SourceAddress:[00-15-5E-7D-3B-37] + Ipv4: Src = 10.121.60.4, Dest = 10.121.193.2, Next Protocol = UDP, Packet ID = 24115, Total IP Length = 346 + Udp: SrcPort = BOOTP server(67), DstPort = BOOTP server(67), Length = 326 - Dhcp: Reply, MsgType = OFFER, TransactionID = 0xD0C789F9 OpCode: Reply, 2(0x02) Hardwaretype: Ethernet HardwareAddressLength: 6 (0x6) HopCount: 0 (0x0) TransactionID: 3502737913 (0xD0C789F9) Seconds: 0 (0x0) + Flags: 0 (0x0) ClientIP: 0.0.0.0 YourIP: 10.121.193.14 ServerIP: 10.121.60.44 RelayAgentIP: 10.121.193.2 + ClientHardwareAddress: 58-E6-BA-3E-8B-7E ServerHostName: BootFileName: boot\x86\wdsnbp.com MagicCookie: 99.130.83.99 + MessageType: OFFER - Type 53 + SubnetMask: 255.255.255.0 - Type 1 + RenewTimeValue: Subnet Mask: 0 day(s),4 hour(s) 0 minute(s) 0 second(s) - Type 58 + RebindingTimeValue: Subnet Mask: 0 day(s),7 hour(s) 0 minute(s) 0 second(s) - Type 59 + IPAddressLeaseTime: Subnet Mask: 0 day(s),8 hour(s) 0 minute(s) 0 second(s) - Type 51 + ServerIdentifier: 10.121.60.4 - Type 54 + Router: 10.121.193.1 - Type 3 + DomainNameServer: 0.0.175717400.175717380 - Type 6 + DHCPEOptionsVendorSpecificInformation: + RelayAgentInfo: - Type 82 + End:

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