• It was determined that the issue occurs when the tunnel creation is sent to L2ALD with the DCI flag set (Flags: 0x20000001) from RPD. After this, no MACLAG Add is received. The MAC Add arrives without the DCI flag, causing L2ALD to reject the remote MAC Add due to a flag mismatch failure. 
• Upon reviewing the configuration, it was identified that the same spines are being used by both DCs and DCI. The leaf switches are using vrf-target auto, which causes them to be treated as a single DC network instead of two separate DCs.
• Suggested that the issue can be resolved by assigning different route targets for the two leaf pairs and applying appropriate policies to prevent route advertisement between DC and VPC networks. 

Considering this was a design flaw we had suggested creating two separate policies: one for DC1 and another for DC2, with specific filter rules for interconnect RT’s and neighbor configurations. The following was the workaround that was shared to the customer - 

Policy to leaf1 and leaf2

set policy-options policy-statement dc1_dci term term1 from family evpn

set policy-options policy-statement dc1_dci term term1 from community dci1-com

set policy-options policy-statement dc1_dci term term1 from community wan-com

set policy-options policy-statement dc1_dci term term1 from community t5-com

set policy-options policy-statement dc1-dci term term1 then accept

set policy-options policy-statement dc1-dci term term2 from family even

set policy-options policy-statement dc1-dci term term2 then reject

set community dci1-com members target:<regular-rt>

set community t5-com members target:<l3-vrf-rt>

set community wan-com members target:<inter-connn-rt>

set protocols bgp group <> neighbor <leaf1> export dc1_dci

set protocols bgp group <> neighbor <leaf2> export dc1_dci

Policy to leaf1 and leaf2

set policy-options policy-statement dc2_dci term term1 from family evpn

set policy-options policy-statement dc2_dci term term1 from community dci2-com

set policy-options policy-statement dc2_dci term term1 from community dwan-com

set policy-options policy-statement dc2_dci term term1 from community t5-com

set policy-options policy-statement dc2-dci term term1 then accept

set policy-options policy-statement dc2-dci term term2 from family even

set policy-options policy-statement dc2-dci term term2 then reject

set community dci2-com members target:<regular-rt-pf-dc2>

set community t5-com members target:<l3-vrf-rt>

set community wan-com members target:<inter-connn-rt>

set protocols bgp group <> neighbor <leaf3> export dc2_dci

set protocols bgp group <> neighbor <leaf4> export dc2_dci