Hi, I’m trying to understand some counterintuitive behaviour I’m seeing with uRPF strict and DHCP on a EX9200/14.2R4.9
According to the documentation[1], uRPF will not, by default, permit DHCP or BOOTP, however the actual behaviour seems to be inconsistent with the documentation: set interfaces ge-0/2/2 speed 1g set interfaces ge-0/2/2 hold-time up 10000 set interfaces ge-0/2/2 hold-time down 0 set interfaces ge-0/2/2 ether-options auto-negotiation set interfaces ge-0/2/2 ether-options no-flow-control set interfaces ge-0/2/2 unit 0 family ethernet-switching interface-mode access set interfaces ge-0/2/2 unit 0 family ethernet-switching vlan members DHCP-TEST set interfaces ge-0/2/2 unit 0 family ethernet-switching storm-control DEFAULT set interfaces ge-0/2/2 unit 0 family ethernet-switching recovery-timeout 60 set vlans DHCP-TEST vlan-id 1000 set vlans DHCP-TEST l3-interface irb.1000 set vlans DHCP-TEST forwarding-options dhcp-security arp-inspection set vlans DHCP-TEST forwarding-options dhcp-security ip-source-guard set interfaces irb unit 1000 family inet rpf-check set interfaces irb unit 1000 family inet address 69.69.69.1/24 set routing-instances INET instance-type vrf set routing-instances INET system services dhcp-local-server group DHCP-TEST interface irb.1000 set routing-instances INET access address-assignment pool DHCP-TEST family inet network 69.69.69.0/24 set routing-instances INET access address-assignment pool DHCP-TEST family inet range DHCP-TEST low 69.69.69.2 set routing-instances INET access address-assignment pool DHCP-TEST family inet range DHCP-TEST high 69.69.69.254 set routing-instances INET access address-assignment pool DHCP-TEST family inet dhcp-attributes name-server 66.207.192.6 set routing-instances INET access address-assignment pool DHCP-TEST family inet dhcp-attributes name-server 206.223.173.7 set routing-instances INET access address-assignment pool DHCP-TEST family inet dhcp-attributes router 69.69.69.1 set routing-instances INET interface irb.1000 set routing-instances INET route-distinguisher 21949:4 set routing-instances INET vrf-target target:21949:4 ario@lab01.juniper# run show dhcp server binding routing-instance INET [edit] ario@lab01.juniper# run show arp vpn INET [edit] ario@lab01.juniper# After I run dhclient on my Linux box, I’m served a lease with no issues at all: ario@lab01.juniper# run show dhcp server binding routing-instance INET IP address Session Id Hardware address Expires State Interface 69.69.69.5 15 00:0c:bd:08:80:9d 86370 BOUND irb.1000 [edit] ario@lab01.juniper# run show interfaces irb.1000 extensive | match RPF Flags: Sendbcast-pkt-to-re, uRPF RPF Failures: Packets: 0, Bytes: 0 [edit] ario@lab01.juniper# run show arp vpn INET MAC Address Address Name Interface Flags 00:0c:bd:08:80:9d 69.69.69.5 nj-69-69-69-5.sta.embarqh irb.1000 [ge-0/2/2.0] none [edit] ario@lab01.juniper# While I don’t see any specific reference in the docs to differences in behaviour using irb interfaces, is it possible there are in fact differences and I just haven’t found the correct docs that outline what they are? Or is there something else that I’m missing? [1]http://www.juniper.net/documentation/en_US/junos14.2/topics/usage-guidelines/interfaces-configuring-unicast-rpf.html Thanks in advance! _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp