No DHCP on pfSense VLAN with Cisco Smart Switch
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@mvikman yeah he has gone to older firmware at one point
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@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. -
@Cannondale
i tought the same. Johnpoz is great.can you post the whole page of the vlan 10 interface configuration on the firewall ?
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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.
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@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
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@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. -
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.
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@pete35
wireshark doesn't seem to be noob friendly. I'm in a "packets must be specified" loop! -
@pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:
Maybe we can do another configuration
Working on it now
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@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.
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@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. -
@Cannondale said in No DHCP on pfSense VLAN with Cisco Smart Switch:
wireshark doesn't seem to be noob friendly. I'm in a "packets must be specified" loop!
@Cannondale
this sounds interesting. if you startup wireshark on your interface of a workstation, it should work out of the box. So maybe there is something crazy on your network at all. Did you select the correct running interface?if you generate a tcpdump file with "tcpdump -i interface -e -w dumpfile.pcap" you can open it with wireshark and you can save captured wireshark packets into a file for later analysis.
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@pete35
Plugged the test Linux workstation into switch port 20 (vlan20).
I was able to create a dumpfile.pcap file on pfSense and open it on another machine in Wireshark. As a non-Network Engineer, what should I look for? -
@pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:
if you startup wireshark on your interface of a workstation, it should work out of the box.
This is what I was seeing after entering some host information:
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looks like it needs some more parameters on startup or needs some more priviledges (root?)
check the "-c" parameter and maybe check all this here:
https://adamtheautomator.com/wireshark-linux/ -
@Cannondale said in No DHCP on pfSense VLAN with Cisco Smart Switch:
Plugged the test Linux workstation into switch port 20 (vlan20).
Do you need another vlan ? Or is this just for investigation?
You can configure another vlan with the same trick, if you have more interfaces on the pfsense.If you can, you may wipe out the whole configuration on the switch and reset it to an initial state. Configure it then only on the GUI. There are a lot of configuration options, maybe not shown on the cli. So if something is hidden, it may influence this crazy vlan issue.
https://www.cisco.com/c/dam/en/us/td/docs/switches/lan/csbss/sf_sg250/quick_start/guide/en_US/78-100762-01A0.pdf
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@pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:
Do you need another vlan ? Or is this just for investigation?
Both. Ultimately need to confirm whether the switch is having an issue with tags. If not a config issue, I will replace it.
@pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:
You can configure another vlan with the same trick, if you have more interfaces on the pfsense.
Understood. I'm not a network expert but I recall that this is called segmentation. My quad port card in the pfSence server is full now. It appears that using additional NIC ports to segregate the LAN is a hardware approach as opposed to the vlan approach. My preference would be to use vlans unless a particular use case suggests that segmentation would work better.
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@pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:
looks like it needs some more parameters on startup or needs some more priviledges (root?)
check the "-c" parameter and maybe check all this here:
https://adamtheautomator.com/wireshark-linux/Thanks for the link! I'll check it out.
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@Cannondale I just skimmed this thread so I may have missed it but have you tried putting 2 ports in the same vlan and see if they can communicate?
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@Jarhead said in No DHCP on pfSense VLAN with Cisco Smart Switch:
have you tried putting 2 ports in the same vlan and see if they can communicate?
Thanks for chiming in Jarhead. Yes. Two untagged ports can communicate on a vlan. One connected to pfSense and the other connected to a Linux workstation.
