Default Cumulus Linux ACL Configuration

The Cumulus Linux default ACL configuration is split into three parts: iptables, ip6tables, and ebtables. The sections below describe the default configurations for each part. You can see the default file by clicking the Default ACL Configuration link:

Default ACL Configuration

iptables

Action/Value Protocol/IP Address
Drop
Destination IP: Any
Source IPv4:
240.0.0.0/5
loopback/8
224.0.0.0/4
255.255.255.255
Set class: 7
Police: Packet rate 2000 burst 2000
Source IP: Any
Destination IP: Any
Protocol:
UDP/BFD Echo
UDP/BFD Control
UDP BFD Multihop Control
OSPF
TCP/BGP (spt dpt 179)
TCP/MLAG (spt dpt 5342)
Set Class: 6
Police: Rate 300 burst 100
Source IP: Any
Destination IP: Any
Protocol:
IGMP
Set class: 2
Police: Rate 100 burst 40
Source IP : Any
Destination IP: Any
Protocol:
ICMP
Set class: 2
Police: Rate 100 burst 100
Source IP: Any
Destination IP: Any
Protocol:
UDP/bootpc, bootps
Set class: 0
Police: Rate 1000 burst 1000
Source IP: Any
Destination IP: Any
ADDRTYPE match dst-type LOCAL
Note: LOCAL is any local address -> Receiving a packet with a destination matching a local IP address on the switch will go to the CPU.
Set class: 0
Police: Rate 400 burst 100
Source IP: Any
Destination IP: Any
ADDRTYPE match dst-type IPROUTER
Note: IPROUTER is any unresolved address -> On a l2/l3 boundary receiving a packet from L3 and needs to go to CPU in order to ARP for the destination.
Set class 0All

Set class is internal to the switch - it does not set any precedence bits.

ip6tables

Action/Value Protocol/IP Address
DropSource IPv6:
ff00::/8
::
::ffff:0.0.0.0/96
localhost
Set class: 7
Police: Packet rate 2000 burst 2000
Source IPv6: Any
Destination IPv6: Any
Protocol:
UDP/BFD Echo
UDP/BFD Control
UDP BFD Multihop Control
OSPF
TCP/BGP (spt dpt 179)
Set class: 6
Police: Packet Rte: 200 burst 100
Source IPv6: Any
Destination IPv6: Any
Protocol:
Multicast Listener Query (MLD)
Multicast
Listener Report (MLD)
Multicast Listener Done (MLD
Multicast Listener Report V2
Set class: 2
Police: Packet rate: 100 burst 100
Source IPv6: Any
Destination IPv6: Any
Protocol:
ipv6-icmp router-solicitation
Set class: 2
Police: Packet rate: 500 burst 500
Source IPv6: Any
Destination IPv6: Any
Protocol:
ipv6-icmp router-advertisement POLICE
Set class: 2
Police: Packet rate: 400 burst 400
Source IPv6: Any
Destination IPv6: Any
Protocol:
ipv6-icmp neighbour-solicitation
ipv6-icmp neighbour-advertisement
Set class: 2
Police: Packet rate: 64 burst: 40
Source IPv6: Any
Destination IPv6: Any
Protocol:
Ipv6 icmp
Set class: 2
Police: Packet rate: 100 burst: 100
Source IPv6: Any
Destination IPv6: Any
Protocol:
UDP/dhcpv6-client:dhcpv6-server (Spts & dpts)
Police: Packet rate: 1000 burst 1000
Source IPv6: Any
Destination IPv6: Any
ADDRTYPE match dst-type LOCAL
Note: LOCAL is any local address -> Receiving a packet with a destination matching a local IPv6 address on the switch will go to the CPU.
Set class: 0
Police: Packet rate: 400 burst 100
ADDRTYPE match dst-type IPROUTER
Note: IPROUTER is an unresolved address -> On a l2/l3 boundary receiving a packet from L3 and needs to go to CPU in order to ARP for the destination.
Set class 0All

Set class is internal to the switch - it does not set any precedence bits.

ebtables

Action/ValueProtocol/MAC Address
Set Class: 7
Police: packet rate: 2000 burst rate:2000
Any switchport input interface
BDPU
LACP=
Cisco PVST
Set Class: 6
Police: packet rate: 200 burst rate: 200
Any switchport input inteface
LLDP
CDP
Set Class: 2
Police: packet rate: 400 burst rate: 100
Any switchport input interface
ARP
Catch All:
Allow all traffic
Any switchport input interface
IPv4
IPv6
Catch All (applied at end):
Set class: 0
Police: packet rate 100 burst rate 100
Any switchport
ALL OTHER

Set class is internal to the switch. It does not set any precedence bits.

Considerations

Due to a hardware limitation on Trident3 switches, certain broadcast packets that are VXLAN decapsulated and sent to the CPU do not hit the normal INPUT chain ACL rules installed with cl-acltool.

You can configure policers for broadcast packets in the /etc/cumulus/switchd.conf file. The policers configuration format and default value is shown below:

cumulus@switch:~$ sudo cat /etc/cumulus/switchd.conf
...
#hal.bcm.vxlan_policers = tunnel_arp=400,tunnel_dhcp_v4=100,tunnel_dhcp_v6=100,tunnel_ttl1=100,tunnel_rs=300,tunnel_ra=300,tunnel_ns=300,tunnel_na=300,local_arp=400,local_rs=300,local_ra=300,local_ns=300,local_na=300