Switching

Hello,

I'm fairly new to Juniper (a few weeks since I started working with it) and I'm currently trying to manually configure a VXLAN tunnel between 2 EX4600 switches.

I started from the bottom, trying a basic configuration to see how it should be configured (used this tutorial: https://www.juniper.net/documentation/en_US/junos/topics/topic-map/vxlan-qfx-series.html#id-example-configuring-a-vxlan-layer-2-gateway), but sadly the vxlan tunnel between my switches doesn't come up. When I check everything that the tutorial says to look at to make sure the tunnel is working, nothing shows up, so the tunnel doesn't work (my configurations and outputs are at the end of this post).

I have read most of the forum posts regarding vxlan and all the tutorials possible, but nothing is helping. Can anyone, please, help me out and tell me what I do wrong or why isn't my tunnel coming up? 

Thank you!

Best regards,

Alex

------------------------------------------------------------

EX4600 switch A configurations:

L3 interface: show interfaces et-0/0/24
unit 0 {
     family inet {
         address 192.168.20.1/24;
    }
         }

Loopback interface (VTEP): show interfaces lo0
unit 0 {
     family inet {
        address 10.2.2.1/32;
     }

L2 interface: show interfaces ge-0/0/0
unit 0 {

        family ethernet-switching {
           interface-mode trunk;
           vlan {
              members v100;
            }
            storm-control default;
        }
}

VLAN: 
v100 {
        vlan-id 100;
        vxlan {
           vni 100;
           multicast-group 233.252.0.2;
           encapsulate-inner-vlan;
           unreachable-vtep-aging-timer 600;
        }
}

VTEP: show switch-options
vtep-source-interface lo0.0;

PIM: show protocols pim
rp {
   static {
      address 30.0.0.1;
   }
}
interface lo0.0;
interface et-0/0/24.0;

OSPF: show protocols ospf
area 0.0.0.0 {
     interface lo0.0;
     interface et-0/0/24.0;
}

Same configurations on Switch B with

• L3 interface: et-0/0/26 - @192.168.20.2/24
• Loopback interface (VTEP): lo0 - @10.2.2.2/32
• L2 interface: ge-0/0/20 

Outputs: 

show ethernet-switching table

I have nothing, no VTEP interface to direct to my vlan. 

show ethernet-switching vxlan-tunnel-end-point source

Logical      System Name     Id    SVTEP-IP     IFL        L3-Idx
<default>                              0      10.2.2.1     lo0.0         0
        L2-RTT              Bridge Domain       VNID       MC-Group-IP
        default-switch        100+100            100          233.252.0.2

show ethernet-switching vxlan-tunnel-end-point remote
Logical        System Name      Id          SVTEP-IP      IFL      L3-Idx
<default>                                 0            10.2.2.1      lo0.0       0

show interfaces vtep

Physical interface: vtep, Enabled, Physical link is Up
     Interface index: 641, SNMP ifIndex: 506
     Type: Software-Pseudo, Link-level type: VxLAN-Tunnel-Endpoint, MTU: Unlimited,
     Speed: Unlimited 
     Device flags : Present Running
     Link type : Full-Duplex
     Link flags : None
     Last flapped : Never
        Input packets : 0
        Output packets: 0

Logical interface vtep.32768 (Index 557) (SNMP ifIndex 515)

      Flags: Up SNMP-Traps Encapsulation: ENET2

      VXLAN Endpoint Type: Source, VXLAN Endpoint Address: 10.2.2.1, L2 Routing Instance: default-switch, L3 Routing Instance: default

     Input packets : 0
     Output packets: 0

show ospf neighbor
Address            Interface       State        ID           Pri        Dead
192.168.20.2   et-0/0/24.0   Full     10.2.2.2    128         37

Hi,

I would suggest to check if the PIM neighborship is working fine and multicast is working on both the devices.

If pim/multicast is working then once you learn the mac address locally will be seen learned via vtep on the other side.

Hope this helps

Hello,

Thank you very much for your reply. 

I have verified if my PIM is working on both devices and I can see their neighbors and the multicast group and rp are correctly configured on both of them...

Outputs: 

show arp
MAC Address              Address            Name              Interface           Flags
3c:8c:93:60:a0:83     192.168.1.1     192.168.1.1     em2.32768       none
3c:8c:93:60:d2:a3     192.168.20.2   192.168.20.2   et-0/0/24.0      none

show pim neighbors

Instance: PIM.master

Interface         IP    V       Mode          Option        Uptime        Neighbor addr
et-0/0/24.0    4     2      HPLGT                           21:41:52       192.168.20.2

show pim join
Instance: PIM.master Family: INET

Group: 233.252.0.2
Source: *
RP: 30.0.0.1
Flags: sparse,rptree,wildcard
Upstream interface: unknown (no nexthop)

show pim interfaces

Name            Stat         Mode         IP         V        State                       NbrCnt        JoinCnt(sg/*g)       DR address
et-0/0/24.0  Up              S              4         2         NotDR,NotCap           1                   0/0                  192.168.20.2
lo0.0              Up              S              4         2         DR,NotCap                 0                    0/0                  10.2.2.1
pime.32769 Down          S             4          2         P2P,NotCap               0                     0/0

show pim source
Instance: PIM.master Family: INET

Source 30.0.0.1
Prefix unknown
Upstream interface unknown
Upstream neighbor unknown

The statistics for pim show they have sent each other Hello messages, but that it is, the rest is at 0. I was thinking that might be the problem, since there is no other communication done between the 2. What I don't understand is what could cause this? 

PIM Message type            Received            Sent             Rx errors
V2 Hello                               2759                2765                 0

Hi Raualex,

Please check out the below KB which has a little more details regarding the pim outputs to check and compare

https://kb.juniper.net/InfoCenter/index?page=content&id=KB30315

Hope this helps.

Hello raviky, 

Thank you once again for replying. 

I have tried this exact configuration and it worked, some configurations had to be changed in order for the VXLAN and PIM to work though. I changed the configuration for PIM interfaces and instead of only adding the interfaces I use, I added all the interfaces. Having only the interfaces I use in PIM wasn't working. 

Thank you for your help. I spent a few days on VXLAN and had no idea where to look, so thank you for telling me to check PIM and multicast. 

Kudos to you ! 

Best regards,

Alex

Glad to know that the issue is resolved.

If possible please share the exact config change that you did in your setup with respect to multicast so that we can update the KB article accordingly.

Sure, no problem.

All that I changed was in PIM regarding the interfaces. 

Instead of having:

set protocols pim interface xe-0/0/2.0 mode sparse

I added:

set protocols pim interface all mode sparse 

I also tried to add only the L3 and the loopback interfaces to PIM and it seems to work too: 

set protocols pim interface xe-0/0/2.0 mode sparse

set protocols pim interface lo0.0 mode sparse

The problem was that one of the interfaces was missing from the PIM configuration.