If the ESI configured on PE devices are different, then default "__default_evpn__.evpn.0 " table won't import the Type 4 route of redudant PE. This causes inconsisent behaviour which may impact in DF election process and show unexpected results.
In the below example R4 and R6 are EVPN PE devices ( this behaviour is aplicatiable for VXLAN EVPN too).
root@R4_re# show interfaces ae0
description ************************Interface-for-EVPN-All-Active******************;
flexible-vlan-tagging;
encapsulation flexible-ethernet-services;
esi {
00:00:02:00:00:00:00:30:00:00;
all-active;
}
root@R6_re# show interfaces ae0
description ************************Interface-for-EVPN-All-Active******************;
flexible-vlan-tagging;
encapsulation flexible-ethernet-services;
esi {
00:00:02:00:00:00:00:30:00:00;
all-active;
}
Here __default_evpn__.evpn.0 shows Type 4 route imported from redudant PE devies (R4).
root@R6_re# run show route table __default_evpn__.evpn.0
__default_evpn__.evpn.0: 3 destinations, 4 routes (3 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both
1:6.6.6.6:0::0200000000300000::FFFF:FFFF/304
*[EVPN/170] 19:19:40
Indirect
4:4.4.4.4:0::0200000000300000:4.4.4.4/304
*[BGP/170] 00:05:43, localpref 100, from 17.17.17.17
AS path: I, validation-state: unverified
> to 34.34.34.1 via ge-0/0/4.0, label-switched-path LSP-R4
[BGP/170] 00:05:43, localpref 100, from 18.18.18.18
AS path: I, validation-state: unverified
> to 34.34.34.1 via ge-0/0/4.0, label-switched-path LSP-R4
4:6.6.6.6:0::0200000000300000:6.6.6.6/304
*[EVPN/170] 19:19:40
Indirect
After changing ESI to 00:00:02:00:00:00:00:40:00:00 on R4.
root@R4_re# show interfaces ae0
Dec 29 04:08:07
flexible-vlan-tagging;
encapsulation flexible-ethernet-services;
esi {
00:00:02:00:00:00:00:40:00:00;
all-active;
}
There is no Type 4 route of R4 installed in __default_evpn__.evpn.0 of R6.
[edit]
root@R6_re# run show route table __default_evpn__.evpn.0
__default_evpn__.evpn.0: 2 destinations, 2 routes (2 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both
1:6.6.6.6:0::0200000000300000::FFFF:FFFF/304
*[EVPN/170] 19:21:34
Indirect
4:6.6.6.6:0::0200000000300000:6.6.6.6/304
*[EVPN/170] 19:21:34
Indirect
Both R4 and R6 are elected as DF as per below output.
[edit]
root@R4_re# run show evpn instance EVPN-182 extensive
Dec 29 04:09:36
Instance: EVPN-182
Route Distinguisher: 4.4.4.4:4002
Per-instance MAC route label: 299808
MAC database status Local Remote
MAC advertisements: 1 4
MAC+IP advertisements: 1 4
Default gateway MAC advertisements: 1 3
Number of local interfaces: 1 (1 up)
Interface name ESI Mode Status
ae0.182 00:00:02:00:00:00:00:40:00:00 all-active Up
Number of IRB interfaces: 1 (1 up)
Interface name VLAN VNI Status L3 context
irb.182 182 Up vrf
Number of bridge domains: 1
VLAN VNI Intfs / up IRB intf Mode MAC sync IM route label
182 None 1 1 irb.182 Extended Enabled 302688
Number of neighbors: 3
3.3.3.3
Received routes
MAC address advertisement: 2
MAC+IP address advertisement: 2
Inclusive multicast: 1
Ethernet auto-discovery: 2
5.5.5.5
Received routes
MAC address advertisement: 1
MAC+IP address advertisement: 1
Inclusive multicast: 1
Ethernet auto-discovery: 2
6.6.6.6
Received routes
MAC address advertisement: 1
MAC+IP address advertisement: 1
Inclusive multicast: 1
Ethernet auto-discovery: 2
Number of ethernet segments: 3
ESI: 00:00:01:00:00:00:00:30:00:00
Status: Resolved by NH 1048614
Number of remote PEs connected: 2
Remote PE MAC label Aliasing label Mode
5.5.5.5 299936 299936 all-active
3.3.3.3 299936 299936 all-active
ESI: 00:00:02:00:00:00:00:30:00:00
Status: Resolved by NH 1048582
Number of remote PEs connected: 1
Remote PE MAC label Aliasing label Mode
6.6.6.6 299936 299936 all-active
ESI: 00:00:02:00:00:00:00:40:00:00
Status: Resolved by IFL ae0.182
Local interface: ae0.182, Status: Up/Forwarding
Designated forwarder: 4.4.4.4 >>>>>>>>>>>>>>>>>>>Elected as DF
Advertised MAC label: 302624
Advertised aliasing label: 302624
Advertised split horizon label: 302656
On R6:
[edit]
root@R6_re# run show evpn instance EVPN-182 extensive
Dec 29 04:11:55
Instance: EVPN-182
Route Distinguisher: 6.6.6.6:4002
Per-instance MAC route label: 299808
MAC database status Local Remote
MAC advertisements: 1 4
MAC+IP advertisements: 1 4
Default gateway MAC advertisements: 1 3
Number of local interfaces: 1 (1 up)
Interface name ESI Mode Status
ae0.182 00:00:02:00:00:00:00:30:00:00 all-active Up
Number of IRB interfaces: 1 (1 up)
Interface name VLAN VNI Status L3 context
irb.182 182 Up vrf
Number of bridge domains: 1
VLAN VNI Intfs / up IRB intf Mode MAC sync IM route label
182 None 1 1 irb.182 Extended Enabled 302096
Number of neighbors: 3
3.3.3.3
Received routes
MAC address advertisement: 2
MAC+IP address advertisement: 2
Inclusive multicast: 1
Ethernet auto-discovery: 2
4.4.4.4
Received routes
MAC address advertisement: 1
MAC+IP address advertisement: 1
Inclusive multicast: 1
Ethernet auto-discovery: 2
5.5.5.5
Received routes
MAC address advertisement: 1
MAC+IP address advertisement: 1
Inclusive multicast: 1
Ethernet auto-discovery: 2
Number of ethernet segments: 3
ESI: 00:00:01:00:00:00:00:30:00:00
Status: Resolved by NH 1048615
Number of remote PEs connected: 2
Remote PE MAC label Aliasing label Mode
3.3.3.3 299936 299936 all-active
5.5.5.5 299936 299936 all-active
ESI: 00:00:02:00:00:00:00:30:00:00
Status: Resolved by IFL ae0.182
Local interface: ae0.182, Status: Up/Forwarding
Designated forwarder: 6.6.6.6 >>>>>>>>>>>>>>>>>>> Elected as DF
Advertised MAC label: 299936
Advertised aliasing label: 299936
Advertised split horizon label: 302080
ESI: 00:00:02:00:00:00:00:40:00:00
Status: Resolved by NH 1048581
Number of remote PEs connected: 1
Remote PE MAC label Aliasing label Mode
4.4.4.4 302272 302624 all-active