I am analyzing ARP responder feature in ODL using openstack.
Am using one control and 2 compute nodes.
Created two networks (tenant1 and tenant2)

While Adding router interface with tenant1 , arp flows are installed both control and compute nodes as expected for DHCP port and default gateway.

And then, if I added router interface with tenant2, in control node arp flows are installed as expected, but, in compute nodes teanant1 default gateway IP is overwritten with teanant2 default gateway IP.

Please find below dump flows:

Added Router interface with tenant1 (10.0.0.0/24)

Control node :

cookie=0x0, duration=496.642s, table=0, n_packets=3, n_bytes=258, priority=0 actions=goto_table:20
cookie=0x0, duration=76.476s, table=20, n_packets=0, n_bytes=0, priority=1024,arp,tun_id=0x412,arp_tpa=10.0.0.2,arp_op=1 actions=move:NXM_OF_ETH_SRC[]>NXM_OF_ETH_DST[],set_field:fa:16:3e:a4:7b:03>eth_src,load:0x2->NXM_OF_ARP_OP[],move:NXM_NX_ARP_SHA[]>NXM_NX_ARP_THA[],move:NXM_OF_ARP_SPA[]>NXM_OF_ARP_TPA[],load:0xfa163ea47b03->NXM_NX_ARP_SHA[],load:0xa000002->NXM_OF_ARP_SPA[],IN_PORT
cookie=0x0, duration=45.164s, table=20, n_packets=0, n_bytes=0, priority=1024,arp,tun_id=0x400,arp_tpa=20.0.0.2,arp_op=1 actions=move:NXM_OF_ETH_SRC[]>NXM_OF_ETH_DST[],set_field:fa:16:3e:3c:f1:d5>eth_src,load:0x2->NXM_OF_ARP_OP[],move:NXM_NX_ARP_SHA[]>NXM_NX_ARP_THA[],move:NXM_OF_ARP_SPA[]>NXM_OF_ARP_TPA[],load:0xfa163e3cf1d5->NXM_NX_ARP_SHA[],load:0x14000002->NXM_OF_ARP_SPA[],IN_PORT
cookie=0x0, duration=2.998s, table=20, n_packets=0, n_bytes=0, priority=1024,arp,tun_id=0x412,arp_tpa=10.0.0.1,arp_op=1 actions=move:NXM_OF_ETH_SRC[]>NXM_OF_ETH_DST[],set_field:fa:16:3e:a4:bf:1b>eth_src,load:0x2->NXM_OF_ARP_OP[],move:NXM_NX_ARP_SHA[]>NXM_NX_ARP_THA[],move:NXM_OF_ARP_SPA[]>NXM_OF_ARP_TPA[],load:0xfa163ea4bf1b->NXM_NX_ARP_SHA[],load:0xa000001->NXM_OF_ARP_SPA[],IN_PORT
cookie=0x0, duration=496.642s, table=20, n_packets=16, n_bytes=1296, priority=0 actions=goto_table:30

Compute1:

cookie=0x0, duration=314.362s, table=0, n_packets=10, n_bytes=788, priority=0 actions=goto_table:20
cookie=0x0, duration=8.498s, table=20, n_packets=0, n_bytes=0, priority=1024,arp,tun_id=0x412,arp_tpa=10.0.0.1,arp_op=1 actions=move:NXM_OF_ETH_SRC[]>NXM_OF_ETH_DST[],set_field:fa:16:3e:a4:bf:1b>eth_src,load:0x2->NXM_OF_ARP_OP[],move:NXM_NX_ARP_SHA[]>NXM_NX_ARP_THA[],move:NXM_OF_ARP_SPA[]>NXM_OF_ARP_TPA[],load:0xfa163ea4bf1b->NXM_NX_ARP_SHA[],load:0xa000001->NXM_OF_ARP_SPA[],IN_PORT
cookie=0x0, duration=314.362s, table=20, n_packets=10, n_bytes=788, priority=0 actions=goto_table:30

Compute2:

cookie=0x0, duration=313.912s, table=0, n_packets=10, n_bytes=788, priority=0 actions=goto_table:20
cookie=0x0, duration=14.214s, table=20, n_packets=0, n_bytes=0, priority=1024,arp,tun_id=0x412,arp_tpa=10.0.0.1,arp_op=1 actions=move:NXM_OF_ETH_SRC[]>NXM_OF_ETH_DST[],set_field:fa:16:3e:a4:bf:1b>eth_src,load:0x2->NXM_OF_ARP_OP[],move:NXM_NX_ARP_SHA[]>NXM_NX_ARP_THA[],move:NXM_OF_ARP_SPA[]>NXM_OF_ARP_TPA[],load:0xfa163ea4bf1b->NXM_NX_ARP_SHA[],load:0xa000001->NXM_OF_ARP_SPA[],IN_PORT
cookie=0x0, duration=313.912s, table=20, n_packets=10, n_bytes=788, priority=0 actions=goto_table:30

Added Router interface with tenant2 (20.0.0.0/24)

Control:

cookie=0x0, duration=591.999s, table=0, n_packets=3, n_bytes=258, priority=0 actions=goto_table:20
cookie=0x0, duration=140.521s, table=20, n_packets=0, n_bytes=0, priority=1024,arp,tun_id=0x400,arp_tpa=20.0.0.2,arp_op=1 actions=move:NXM_OF_ETH_SRC[]>NXM_OF_ETH_DST[],set_field:fa:16:3e:3c:f1:d5>eth_src,load:0x2->NXM_OF_ARP_OP[],move:NXM_NX_ARP_SHA[]>NXM_NX_ARP_THA[],move:NXM_OF_ARP_SPA[]>NXM_OF_ARP_TPA[],load:0xfa163e3cf1d5->NXM_NX_ARP_SHA[],load:0x14000002->NXM_OF_ARP_SPA[],IN_PORT
cookie=0x0, duration=171.833s, table=20, n_packets=0, n_bytes=0, priority=1024,arp,tun_id=0x412,arp_tpa=10.0.0.2,arp_op=1 actions=move:NXM_OF_ETH_SRC[]>NXM_OF_ETH_DST[],set_field:fa:16:3e:a4:7b:03>eth_src,load:0x2->NXM_OF_ARP_OP[],move:NXM_NX_ARP_SHA[]>NXM_NX_ARP_THA[],move:NXM_OF_ARP_SPA[]>NXM_OF_ARP_TPA[],load:0xfa163ea47b03->NXM_NX_ARP_SHA[],load:0xa000002->NXM_OF_ARP_SPA[],IN_PORT
cookie=0x0, duration=98.355s, table=20, n_packets=0, n_bytes=0, priority=1024,arp,tun_id=0x412,arp_tpa=10.0.0.1,arp_op=1 actions=move:NXM_OF_ETH_SRC[]>NXM_OF_ETH_DST[],set_field:fa:16:3e:a4:bf:1b>eth_src,load:0x2->NXM_OF_ARP_OP[],move:NXM_NX_ARP_SHA[]>NXM_NX_ARP_THA[],move:NXM_OF_ARP_SPA[]>NXM_OF_ARP_TPA[],load:0xfa163ea4bf1b->NXM_NX_ARP_SHA[],load:0xa000001->NXM_OF_ARP_SPA[],IN_PORT
cookie=0x0, duration=8.945s, table=20, n_packets=0, n_bytes=0, priority=1024,arp,tun_id=0x400,arp_tpa=20.0.0.1,arp_op=1 actions=move:NXM_OF_ETH_SRC[]>NXM_OF_ETH_DST[],set_field:fa:16:3e:e6:97:f1>eth_src,load:0x2->NXM_OF_ARP_OP[],move:NXM_NX_ARP_SHA[]>NXM_NX_ARP_THA[],move:NXM_OF_ARP_SPA[]>NXM_OF_ARP_TPA[],load:0xfa163ee697f1->NXM_NX_ARP_SHA[],load:0x14000001->NXM_OF_ARP_SPA[],IN_PORT
cookie=0x0, duration=591.999s, table=20, n_packets=16, n_bytes=1296, priority=0 actions=goto_table:30

Compute1:

cookie=0x0, duration=427.876s, table=0, n_packets=10, n_bytes=788, priority=0 actions=goto_table:20
cookie=0x0, duration=32.892s, table=20, n_packets=0, n_bytes=0, priority=1024,arp,tun_id=0x400,arp_tpa=20.0.0.1,arp_op=1 actions=move:NXM_OF_ETH_SRC[]>NXM_OF_ETH_DST[],set_field:fa:16:3e:e6:97:f1>eth_src,load:0x2->NXM_OF_ARP_OP[],move:NXM_NX_ARP_SHA[]>NXM_NX_ARP_THA[],move:NXM_OF_ARP_SPA[]>NXM_OF_ARP_TPA[],load:0xfa163ee697f1->NXM_NX_ARP_SHA[],load:0x14000001->NXM_OF_ARP_SPA[],IN_PORT
cookie=0x0, duration=427.876s, table=20, n_packets=10, n_bytes=788, priority=0 actions=goto_table:30

Compute2:

cookie=0x0, duration=450.695s, table=0, n_packets=10, n_bytes=788, priority=0 actions=goto_table:20
cookie=0x0, duration=61.874s, table=20, n_packets=0, n_bytes=0, priority=1024,arp,tun_id=0x400,arp_tpa=20.0.0.1,arp_op=1 actions=move:NXM_OF_ETH_SRC[]>NXM_OF_ETH_DST[],set_field:fa:16:3e:e6:97:f1>eth_src,load:0x2->NXM_OF_ARP_OP[],move:NXM_NX_ARP_SHA[]>NXM_NX_ARP_THA[],move:NXM_OF_ARP_SPA[]>NXM_OF_ARP_TPA[],load:0xfa163ee697f1->NXM_NX_ARP_SHA[],load:0x14000001->NXM_OF_ARP_SPA[],IN_PORT
cookie=0x0, duration=450.695s, table=20, n_packets=10, n_bytes=788, priority=0 actions=goto_table:30