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Dynamic VLAN assignment with Radius

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nabz0r    140

Is it possible for a radius server to assign vlan dynamically on a switch port that is on a dummy vlan before it gets authenticated?

 

What I mean if a domain PC connects to a switch port assign vlan 3180 - 3189 (these are client vlans), if it is a printer assign it to vlan 3017 and if it is a guest user assign it to vlan guest and send it to a web portal for registration. Is this even possible or I am thinking way out of the box?

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+BudMan    3,150

There are many ways to assign vlan based upon criteria - mac, auth to radius sure.. What switch(es) do you have?  Your 30$ smart switch not going to be able to do this sort of thing ;)

 

Sounds like your wanting to implement a NAC... Check out https://packetfence.org/

 

If your a cisco shop it would be ICE.. But not free ;)  https://www.cisco.com/c/en/us/products/security/identity-services-engine/index.html

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nabz0r    140

Great, then what I am trying to do will work somehow. Haha, my switch cost almost 1000$ :p

 

I am going to use ISE and what I want to do is: Dot1X and MAB, but if the user is not found in the AD or ISE DB should be redirected to a guest web portal for registration. Now if when I assign the port to a specific vlan for dot1x it works fine, i.e client vlan, but it will not change vlan to guest vlan after the registration is done.

 

So now I want to assign all ports to a dummy vlan i.e 999 and after switch port is authenticated for domain pc's it should move them to client vlan and the same for printer vlan. Guest should be moved from dummy vlan to guest vlan after the registration is done.

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+BudMan    3,150

This is a common setup where device gets dumped into restricted vlan until they auth in some manner, fill out info in a captive portal could sure be one of those options.

 

I am quite sure ISE can do that... I would open up a tac case with cisco if your having problem with specific configuration option not working etc,

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nabz0r    140

Good to know it is possible, have you done this before?

Yeah, I am sure ISE can do it. The problem is that ISE 2.3 they have re-done everything and there aren't a lot of documentation so read and the older ones aren't really applicable.

 

I will open a tac case, but wanted to make sure that it is possible from radius perspective.

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+BudMan    3,150

I have not done it with ISE... But restricted vlan is standard practice... Yes we do this at work..... How do you think the device can talk to anything to auth ;)

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nabz0r    140

What are you using if not ISE? Can you share your switch port and aaa config? Here or you can PM me. :)

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+BudMan    3,150

Sure when I get to work in the morning I will post up some info..

 

Got called so a bit early this morning.. Freaking circuit can not stay up for more 30 days at a time without a freaking issue... Arrrggh ;)

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sc302    1,525
On ‎1‎/‎23‎/‎2018 at 5:27 PM, nabz0r said:

Is it possible for a radius server to assign vlan dynamically on a switch port that is on a dummy vlan before it gets authenticated?

 

What I mean if a domain PC connects to a switch port assign vlan 3180 - 3189 (these are client vlans), if it is a printer assign it to vlan 3017 and if it is a guest user assign it to vlan guest and send it to a web portal for registration. Is this even possible or I am thinking way out of the box?

 

 

Here is what happens in my scenario.

Vlan 1 is an unconfigured vlan.  Vlan1 is essentially shut down. 

If an unauthenticated computer/device somehow holds the port open, that computer/device resides on vlan1.  Vlan1 has no IP or subnet, it routes no where.  Most of the time, if a computer can't auth the port goes into an administrative shutdown state.  If I plug my fluke LinkRunner in, it holds the port in an online status and it gives me the port info and the configured vlan of 1.

 

If a computer gets authenticated, Radius then pushes out what vlan that port can communicate on.

 

I think that is the scenario that you are looking for...a dummy vlan (The default vlan of the switch, which should always remain unconfigured).

 

802.1x doesn't really support a "portal".  You can configure the switch to use the default vlan for all else to belong to a vlan that has portal access (your default vlan for the access port)....

 

in my switch I would do this as an example:

int gi1/0/1

switchport mode access

switchport access vlan 3017

authentication order

authentication port control auto

mab

dot1x pae authenticator

spanning-tree portfast edge

 

This would put all unauthenticated computers on vlan 3017

 

It kind of urks me a little that the 2960x series has a different state of cli instructions, how the x series has depreciated commands where the xr series they continue to live and breathe in.

For you, you may want to look at this and look at the guest vlan settings or 802.1x Authentication with Restricted VLAN:

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960x/software/15-0_2_EX/security/configuration_guide/b_sec_152ex_2960-x_cg/b_sec_152ex_2960-x_cg_chapter_010000.html#ID737

 

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nabz0r    140

@BudMan, I actually have seen that link and he uses NPS, not ISE. I have figured it out and my ISE is now doing all the job with a little help of Ative directory and I am going to use ISE for authentication and command authorization based on AD group for network department, today we're using local username which is NO good.

 

@sc302, Yes, that is the scenario I was looking for. All switch ports are assigned a dummy vlan, though not vlan 1 and when a device gets authenticated ISE will put it in a respective vlan. I even have succeeded with the portal through ISE for guest users/pc. Guests connect to a port, they get redirected to guest portal for registration and then login and have only internet access. As for the portal design, Cisco provides Portal Builder isepb.cisco.com and when you're done with the design, you import it into your ISE like a boss. :D

 

This was a big project and I am happy that everything worked out as I wanted though I've grown 50 new gray hair because of this hehe. If anyone is interested on the product and wants to know how to configure dot1x, man or guest authentication I'd be happy to help, just PM me or write here.

 

My switch config:

interface GigabitEthernet1/0/22
 description GARDSHUSET RICOH AFICIO C430DN
 switchport access vlan 666
 switchport mode access
 switchport nonegotiate
 power inline never
 authentication periodic
 authentication timer reauthenticate server
 access-session control-direction in
 access-session closed
 access-session port-control auto
 mab
 dot1x pae authenticator
 dot1x timeout tx-period 10
 spanning-tree portfast
 service-policy type control subscriber DOT1X_MAB_WEBAUTH_POLICY

 

Polic-map (class-map is also configured)

se08-as11#sh policy-map type control subscriber DOT1X_MAB_WEBAUTH_POLICY
DOT1X_MAB_WEBAUTH_POLICY
  event session-started match-all
    10 class always do-until-failure
      10 authenticate using dot1x priority 10
  event authentication-failure match-first
    5 class DOT1X_FAILED do-until-failure
      10 terminate dot1x
      20 authenticate using mab priority 20
    10 class AAA_SVR_DOWN_UNAUTHD_HOST do-until-failure
      10 clear-authenticated-data-hosts-on-port
      20 activate service-template CRITICAL_AUTH_VLAN
      30 activate service-template DEFAULT_CRITICAL_VOICE_TEMPLATE
      40 authorize
      50 pause reauthentication
    20 class AAA_SVR_DOWN_AUTHD_HOST do-until-failure
      10 pause reauthentication
      20 authorize
    30 class DOT1X_NO_RESP do-until-failure
      10 terminate dot1x
      20 authenticate using mab priority 20
    40 class MAB_FAILED do-until-failure
      10 terminate mab
      20 authentication-restart 60
    60 class always do-until-failure
      10 terminate dot1x
      20 terminate mab
      30 authentication-restart 60
  event agent-found match-all
    10 class always do-until-failure
      10 terminate mab
      20 authenticate using dot1x retries 2 retry-time 0 priority 10
      30 authenticate using dot1x priority 10
  event aaa-available match-all
    10 class IN_CRITICAL_VLAN do-until-failure
      10 clear-session
    20 class NOT_IN_CRITICAL_VLAN do-until-failure
      10 resume reauthentication
  event authentication-success match-all
    10 class always do-until-failure
      10 activate service-template DEFAULT_LINKSEC_POLICY_MUST_SECURE
  event violation match-all
    10 class always do-until-failure
      10 restrict
  event inactivity-timeout match-all
    10 class always do-until-failure
      10 clear-session

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