12-10-2024 02:31 AM - edited 12-10-2024 02:38 AM
Hello everyone!
Please help to get rid of the VXLAN over internet issues.
We have many sites with Nexuses 93180YC-FX (in vPC chassis) and want to combine them into single L2 segment at least for management network.
2 of sites should be route-reflectors the others will be route-reflector-clients.
But current goal is to get VXLAN operational between 2 sites only.
Constraints and pre-requisites:
Common part of the config:
nv overlay evpn
feature bgp
feature interface-vlan
feature vn-segment-vlan-based
feature vpc
feature nv overlay
vlan 3
name VXLANTEST
vn-segment 10003
interface nve1
no shutdown
host-reachability protocol bgp
source-interface loopback0 anycast loopback1
member vni 10003
ingress-replication protocol bgp
router bgp <public ans>
! router-id <local ipv4>
address-family l2vpn evpn
allow-vni-in-ethertag
! neighbors configs...
evpn
vni 10003 l2
rd auto
route-target import auto
route-target export auto
We have sites #6 and #8, so neighbors config are similar except digits 6 & 8. Below is an example of site #6 config:
interface Vlan3
ip address 10.1.6.1/16
interface loopback0
ipv6 address bad:face:6::aaaa/128
interface loopback1
ipv6 address bad:face:6::ba/128
! BGP section below
neighbor bad:face:8::ba
remote-as 65008
local-as 65006
update-source loopback1
disable-connected-check
ebgp-multihop 32
address-family l2vpn evpn
allowas-in 3
send-community
send-community extended
vPC peer has the same config except interface loopback0 — ipv6 address bad:face:6::bbbb/128.
Debug commands and their outputs
# show bgp session
bad:face:8::ba 65008 0 16:14:07|00:00:48|00:00:16 E 179/20558 0/0
SUCCESS: BGP Sessions established
# show bgp l2vpn evpn vni-id 10003
Route Distinguisher: <local bgp router-id>:32770 (L2VNI 10003)
*>l[2]:[0]:[0]:[48]:[062c.2bd4.89dc]:[0]:[0.0.0.0]/216
bad:face:6::ba 100 32768 i
*>e[2]:[0]:[0]:[48]:[c27e.3bf4.23fd]:[0]:[0.0.0.0]/216
bad:face:8::ba 0 65006 65008 202656 i
*>l[3]:[0]:[128]:[bad:face:6::ba]/184
bad:face:6::ba 100 32768 i
*>e[3]:[0]:[128]:[bad:face:8::ba]/184
bad:face:8::ba 0 65006 65008 202656 i
SUCCESS: we see local and remote MAC addresses.
FAIL: We see only MAC route and no MAC-IP routes.
# show mac address-table vlan 3
VLAN MAC Address Type age Secure NTFY Ports
---------+-----------------+--------+---------+------+----+------------------
C 3 c27e.3bf4.23fd dynamic NA F F nve1(bad:face:8::ba)
+ 3 062c.2bd4.89dc dynamic NA F F vPC Peer-Link
SUCCESS: We see remote MAC addresses in the mac address-table.
# show ip arp vlan 3
Address Age MAC Address Interface Flags
10.1.6.2 00:12:07 003a.9c1c.6ae7 Vlan3
10.1.6.253 00:00:03 062c.2bd4.89dc Vlan3 +
10.1.8.2 00:00:19 INCOMPLETE Vlan3
FAIL: we don't see here any entries with remote MAC addresses.
# show nve peers
Interface Peer-IP State LearnType Uptime Router-Mac
--------- -------------------------------------- ----- --------- -------- -----------------
nve1 bad:face:8::ba Up CP 00:19:09 n/a
SUCCESS: we see raised up peer.
FAIL: Router-Mac is n/a (probably that is the reason).
I tried to specify virtual-rmac and advertise it (along with advertise-pip in BGP scope) but have no luck.
Neither switches nor hosts can't ping each other.
Can anyone please advice anything...
12-21-2024 11:07 PM
If your doing this over the internet with VxLan your most likely do not have jumbo frame support. There for your MTU should reflect this. Lots of good info on MTU, BGP mtu discovery and if your looking for L2 extension yes this will work but all the host must have a lower mtu hardcode in their settings.
12-22-2024 12:21 AM
Thank you for your comment! I know this, on my hosts there is already set MTU 1446. But the problem is that BGP doesn’t work as expected. I see Type-2 MAC routes but no MAC-IP ones. Could you advise what to do to make this work?
12-22-2024 02:14 AM
Please provide the entire config due to things that can cause this issue. Why are you doing IPv6? Not saying it will not work but I doubt it being tested as much as IPv4.
what version of nexus?
12-22-2024 02:25 AM
Thank you in advance for your help!
I remove some sensitive data and pasted "show run" command at pastebin.
I use IPv6 because I found that this is the only way to use public IP on loopback interface.
12-22-2024 11:03 PM
To get MAC-IP type-2 routes, please configure SVI as anycast gateway
12-23-2024 12:14 AM
Thank you for the hint Pavel!
Added the following on two vPC peers at site #6 (the same with mac ...0008 on site #8):
fabric forwarding anycast-gateway-mac 0000.face.0006
int vlan3
fabric forwarding mode anycast-gateway
But unfortunately nothing changed
12-23-2024 12:22 AM
Please add vrf member configuration and configure VRF/L3VNI for tenants accordingly.
12-23-2024 12:46 AM
Can you please advise what exactly I should do?
At int nve1 level I already have:
member vni 10003
ingress-replication protocol bgp
Should I remove this and add member vni 10003 associate-vrf instead? I can't override it, got en error "Cannot associate a multicast group or vrf to an ingress replication vni".
I have added the following block:
vrf context VXLAN
vni 10003
rd auto
address-family ipv4 unicast
route-target both auto
route-target both auto evpn
And now I see changes in show bgp l2vpn evpn command but still no MAC-IP routes.
Route Distinguisher: 31.134.200.150:6 (L3VNI 10003)
e[2]:[0]:[0]:[48]:[c27e.3bf4.23fd]:[0]:[0.0.0.0]/216
2a13:f580:8::ba 0 65006 65008 202656 i
e[3]:[0]:[128]:[2a13:f580:8::ba]/184
2a13:f580:8::ba 0 65006 65008 202656 i
12-23-2024 12:55 AM
For L3VNI you need new VLAN and VRF, like:
vlan 10
vn-segment 10010
vrf context VXLAN
vni 10010
rd auto
address-family ipv4 unicast
route-target both auto
route-target both auto evpn
interface nve 1
member vni 10010 associate-vrf
int vl 10
vrf member VXLAN
ip forward
12-23-2024 01:43 AM
Thanks, I have added this but now do not see L3VNI section in "show bgp l2vpn evpn" output.
12-23-2024 01:55 AM
Please share output for
show nve vni
show nve peers
show ip int br vrf all
show ipv6 int br vrf all
Also, you need to add vlan 3 to BGP ipv4 under vrf
router bgp <AS>
vrf VXLAN
address-family ipv4 uni
network <vlan3 network>
address-family ipv6 uni
And I don't see any ip address under int vl3. Is it configured?
In general, please follow NX-OS VXLAN configuration guide to make it work, as it seems you have configured it only partially, and it's hard to determine which part are missed.
12-23-2024 02:22 AM
show nve vni
Interface VNI Multicast-group State Mode Type [BD/VRF] Flags
--------- -------- ----------------- ----- ---- ------------------ -----
nve1 10003 UnicastBGP Up CP L2 [3]
nve1 10010 n/a Down CP L3 [VXLAN]
show nve peers
Interface Peer-IP State LearnType Uptime Router-Mac
--------- -------------------------------------- ----- --------- -------- -----------------
nve1 2a13:f580:6::ba Up CP 01:55:24 n/a
show ip int br vrf all
IP Interface Status for VRF "default"(1)
Interface IP Address Interface Status
Vlan1 91.216.155.250 protocol-up/link-up/admin-up
Vlan2 10.0.8.250 protocol-up/link-up/admin-up
Vlan3 10.1.8.2 protocol-up/link-up/admin-up
Eth1/45 31.28.91.122 protocol-up/link-up/admin-up
! omit non-related
IP Interface Status for VRF "VXLAN"(6)
Interface IP Address Interface Status
Vlan10 forward-enabled protocol-down/link-down/admin-down
show ipv6 int br vrf all
IPv6 Interface Status for VRF "default"(1)
Interface IPv6 Address/Link-local Address Interface Status
prot/link/admin
Vlan1 2a13:f580:8::250 up/up/up
fe80::7e21:eff:fee3:72a7
Lo0 2a13:f580:8::bbbb up/up/up
fe80::7e21:eff:fee3:72a0
Lo1 2a13:f580:8::ba up/up/up
fe80::7e21:eff:fee3:72a0
Eth1/45 2a10:6740::23:2 up/up/up
fe80::7e21:eff:fee3:72a7
! omit non-related
IPv6 Interface Status for VRF "VXLAN"(6)
Interface IPv6 Address/Link-local Address Interface Status
prot/link/admin
Additional settings to BGP has been also added.
VLAN 3 have IP addresses:
rs1-gb: 10.1.8.1/16
rs2-gb: 10.1.8.2/16
rs1-nl: 10.1.6.1/16
rs2-nl: 10.1.8.2/16
By the way, I can ping to/from rs2-gb (where anycast VTEP IPv6 address originate) to rs1-nl!
But it seems after applying anycast-gateway configuration I can't ping vPC peers:
no ping between rs1-gb and rs2-gb (10.1.8.1 and 10.1.8.2).
no ping between rs1-nl and rs2-nl (10.1.6.1 and 10.1.6.2).
12-23-2024 02:34 AM
1) move int vl 3 to vrf VXLAN
int vl 3
vrf member VXLAN
2) Unshut int vl 10, it should move vni 10010 in "sh nve vni" output to up state
3) What interface used for connectivity to NVE peer?
An SVI in any VRF remains not supported as VXLAN uplink.
4) How source loopback for NVE configured?
For VPC it should be configured in specific way:
12-23-2024 03:03 AM
1, 2) Done.
3) sh ru int nve1:
interface nve1
no shutdown
host-reachability protocol bgp
advertise virtual-rmac
virtual-rmac 0000.cafe.0008
source-interface loopback0 anycast loopback1
member vni 10003
ingress-replication protocol bgp
member vni 10010 associate-v
4) sh ru int lo re 0|1
interface loopback0
ipv6 address 2a13:f580:8::bbbb/128
interface loopback1
ipv6 address 2a13:f580:8::ba/128
Also I have changed VLAN3 IP to be the same for local VTEPs and as a result I can't ping that IPs anymore.
Also I discovered some changes in show nve peers. I see non-anycast IPs (that configured on lo0) and MACs of the routers:
rs2-gb# show nve peers
Interface Peer-IP State LearnType Uptime Router-Mac
--------- -------------------------------------- ----- --------- -------- -----------------
nve1 2a13:f580:6::ba Up CP 02:43:33 n/a
nve1 2a13:f580:6::aaaa Up CP 00:19:34 003a.9c17.8e47
rs1-nl# show nve peers
Interface Peer-IP State LearnType Uptime Router-Mac
--------- -------------------------------------- ----- --------- -------- -----------------
nve1 2a13:f580:8::ba Up CP 02:45:59 n/a
nve1 2a13:f580:8::bbbb Up CP 00:20:43 7c21.0ee3.72a7
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