DMVPN and QOS

Cisco, Telecom

How can DMVPN can make some QOS per spoke ?

It is what we will configure today :

Here is the network :

Schema  

 

 

 

I will not explain how NHRP works in detail here.

R1, R2, R3, R4 use IS-IS (for fun) as IGP.

router isis
net 49.MAC_ADD.00

interface etc x/y
ip router isis

Now, here it comes DMVPN configurations :

R4#show run int tun 0
Building configuration...

Current configuration : 351 bytes
!
interface Tunnel0
 bandwidth 1000
 ip address 77.0.0.4 255.255.255.0
 no ip redirects
 ip nhrp authentication 1111
 ip nhrp map multicast dynamic
 ip nhrp map group toto service-policy output pm
 ip nhrp network-id 1111
 ip nhrp redirect
 load-interval 30
 qos pre-classify
 tunnel source Loopback0
 tunnel mode gre multipoint
 tunnel key 1111
end

R4#

And for R3 :

R3#show run int tun 0
Building configuration...

Current configuration : 340 bytes
!
interface Tunnel0
 ip address 77.0.0.3 255.255.255.0
 no ip redirects
 ip nhrp authentication 1111
 ip nhrp group toto
 ip nhrp map 77.0.0.4 4.4.4.4
 ip nhrp map multicast 4.4.4.4
 ip nhrp network-id 1111
 ip nhrp nhs 77.0.0.4
 ip nhrp shortcut
 qos pre-classify
 tunnel source Loopback0
 tunnel mode gre multipoint
 tunnel key 1111
end

R3#

!!! WARNING !!!  ‘ip nhrp group’ and ‘ip nhrp map group xxx service-policy output yyy’ commands are not displayed with ‘?’. But the correct way is ’nhrp group xxx’ and ’nhrp map group xxx service-policy out pm’.

The mapping of the policy-map on the multipoint tunnel is done when the NHRP request is sent (on the spoke we flag it by means of ‘ip nhrp group toto’). Some extra fields in the NHRP packet show that ’this’ kind of trafic through this IP must be grouped with ’this’ spoke.

We can see the mapping by :

4#show dmvpn detail
Legend: Attrb --> S - Static, D - Dynamic, I - Incomplete
	N - NATed, L - Local, X - No Socket
	# Ent --> Number of NHRP entries with same NBMA peer
	NHS Status: E --> Expecting Replies, R --> Responding, W --> Waiting
	UpDn Time --> Up or Down Time for a Tunnel
==========================================================================

Interface Tunnel0 is up/up, Addr. is 77.0.0.4, VRF ""
   Tunnel Src./Dest. addr: 4.4.4.4/MGRE, Tunnel VRF ""
   Protocol/Transport: "multi-GRE/IP", Protect ""
   Interface State Control: Disabled
   nhrp event-publisher : Disabled
Type:Hub, Total NBMA Peers (v4/v6): 2

# Ent  Peer NBMA Addr Peer Tunnel Add State  UpDn Tm Attrb    Target Network
----- --------------- --------------- ----- -------- ----- -----------------
    1 2.2.2.2                77.0.0.2    UP 09:21:51    D        77.0.0.2/32
    1 3.3.3.3                77.0.0.3    UP 09:22:34    D        77.0.0.3/32
NHRP group: toto
 Output QoS service-policy applied: pm

Crypto Session Details:
--------------------------------------------------------------------------------

Pending DMVPN Sessions:

R4#

And we can see statistics by this command :

R4#show policy-map multipoint Tunnel 0 3.3.3.3

Interface Tunnel0  3.3.3.3

  Service-policy output: pm

    Class-map: class-default (match-any)
      8 packets, 1061 bytes
      30 second offered rate 0000 bps, drop rate 0000 bps
      Match: any
R4#