No DHCP on pfSense VLAN with Cisco Smart Switch

[Cannondale]

@mvikman
This is what my menu looks like:

[pete35]

@johnpoz
i cant imaging how this switch shouldnt do vlan tagging correctly. If its defect it wouldnt do anything. There are thousand of SGXXX switches out there, googleing for vlan tagging problems doesnt give any problems at all.

for the tcpdump vlan story: you see the vlan tags if running tcpdump with "-v". With "-w" it goes to a file which can be open with wireshark, vlan tags are not shown there by default.

[johnpoz]

@pete35 its quite possible he is looking at his output from tcpdump wrong? But I was quite clear on how to do it and showed examples.. Its a simple std output to the screen.

I am with you - there are 1000's or even 10s or 100s of thousands of these out there - if there was some issue with vlans you would think it would be easy enough to find people complaining.

I will have one to play with here in a few days ;) As long as it works - it will allow me to get rid of an injector using for my flex HD unifi AP have sitting on my floor in my computer room..

Its an open box off ebay - so you never know. But says fully operational just missing couple of the rubber feet on the bottom ;)

[pete35]

@johnpoz

I would really like to know the issue here. CBS350 or Catalyst 1000 is the better modern choice for this switches. SG250 is really old in terms of Cisco switches. Most of the models arent supported anymore by new firmware versions. Vlans are are working for pfsense and also for this Cisco switch. So there must be a issue between them or on layer 8 maybe.

[Cannondale]

Thanks for your efforts pete35! Very interesting information.
Not familiar with wireshark. Will install it and see what I can find.

I did check the pfSense DHCP log for DHCPREQUEST on the vlan20 IP but don't see anything. Just the entry for "Listening on BPF/igb1"

[pete35]

@johnpoz @Cannondale

pls reboot that switch:

[johnpoz]

@pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:

anymore by new firmware versions

The sg250 seems to have gotten a firmware release quite recent.

My own sg300 hasn't had one since 18-Jun-2020

Pretty sure he has rebooted - since I know he changed firmwares at one point, etc.

[mvikman]

He originally had the latest firmware installed

Roth-SG250-50P-1
v2.5.9.16 / RCBS3.1_930_871_10

Also his latest "show tech" shows that firmware 2.5.9.16 is active

------------------ show version ------------------
Active-image: flash://system/images/image_tesla250_hybrid_2.5.9.16_release_cisco_signed.bin
  Version: 2.5.9.16
  MD5 Digest: c1f283dd662260f1532ef8cb26158014
  Date: 27-Feb-2023
  Time: 16:57:47
Inactive-image: flash://system/images/SG250-50P-Firmware_Backup_v2.4.0.94-image1-20230428.bin
  Version: 2.4.0.94
  MD5 Digest: 6f5be217100f34929986f2e93dd2d5e9
  Date: 31-May-2018
  Time: 02:39:58

[Cannondale]

@mvikman said in No DHCP on pfSense VLAN with Cisco Smart Switch:

He originally had the latest firmware installed

Confirmed the latest fw is active.

[johnpoz]

@mvikman yeah he has gone to older firmware at one point

[Cannondale]

@johnpoz said in No DHCP on pfSense VLAN with Cisco Smart Switch:

Just ordered a sg250-08HP off ebay

You're a stand up guy for going the extra mile johnpoz!
No need to spend your money to help solve my problem!
PM me and let me know how much it was so that I can reimburse you.

[pete35]

@Cannondale
i tought the same. Johnpoz is great.

can you post the whole page of the vlan 10 interface configuration on the firewall ?

[Derelict]

If you pcap on the parent interface you will see all the VLAN tags there along with all traffic on all VLANs. If you pcap on the VLAN interface you will not see the tags.

I sometimes create unnumbered pfSense interfaces on the parent (IPv4 and IPv6 set to None) just so I can pcap there.

[Cannondale]

@pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:

can you post the whole page of the vlan 10 interface configuration on the firewall ?

vlan10 is configured for access mode on ge24
vlan20 is configured for general mode on ge20

[pete35]

@Derelict
thank you. i already found it. Wireshark shows the vlan tag under each packet. yo need to open a packet to see the vlan 802.1q information.

[pete35]

@Cannondale

Maybe we can do another configuration:

if you have a free port on your Pfsense, just configure it as LAN port with the IP address of your VLAN 10, first clear that VLAN 10 interface including that DHCP Server. Then configure two ports on the switch as access port in vlan 10. Connect one port directly to the second/new LAN port of pfsense, the other one to your workstation. You need to configure the DHCP Server at the new LAN port.

Your workstation should be able to get an IP DHCP address from Pfsense in this VLAN 10.

So no tagging is needed, if that is an issue with that switch.

[Cannondale]

@pete35
wireshark doesn't seem to be noob friendly. I'm in a "packets must be specified" loop!

[Cannondale]

@pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:

Maybe we can do another configuration

Working on it now

[Cannondale]

@pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:

Your workstation should be able to get an IP DHCP address from Pfsense in this VLAN 10

Got a vlan10 IP on the workstation. Didn't need to reconfigure the switch for vlan10 as port 23 and 24 were already configured for vlan10.

[pete35]

@Cannondale
That sounds good. Add more vlan 10 access ports to connect your servers and so on.
Until you find another solution with that tagging issue, this is as good as a trunked port and seperates the traffic.
Dont forget to add some firewall rules to limit the access to vlan 10 if you need this. Pfsense will route between Vlans.