Known Behavior
19
Release 10.2.2
When these three conditions exist simultaneously, the ES2 4G LM may not be
able to successfully process all DHCP packets. Although all clients may get
bounded in DHCP relay or relay proxy, some clients may not get bounded in
DHCP external server. (In a production environment it is highly unlikely for
conditions 1 and 2 to exist because stand-alone DHCP external server is
normally configured for a DHCP relay in a different chassis.)
Work-around:
You can eliminate this issue by modifying any one of these
conditions. For example, this issue does not exist with any of the following
configuration modifications:
Configure DHCP external server and either DHCP relay or relay proxy in
the same virtual router.
Configure the client-facing and server-facing interfaces for DHCP external
server and either DHCP relay or relay proxy on the same ES2 10G LM
instead of the same ES2 4G LM.
Configure the client-facing and server-facing interfaces for DHCP external
server and either DHCP relay or relay proxy on separate ES2 4G LMs.
Dynamic Interfaces
Dynamic IPv6 interfaces over static PPP interfaces are not supported.
Ethernet
The hashing algorithm that selects the LAG member link is associated with the
IP address of the subscriber client to support QoS. Consequently, a particular
flow is always hashed to the same link. When a member link is removed from a
LAG bundle, traffic rate is disrupted and traffic flow is reduced. When the link
goes down and then comes back up, the traffic flow is automatically
redistributed.
When counting bits per second on a Fast Ethernet or Gigabit Ethernet interface,
an E Series router includes 12 bytes for interpacket gap, 7 bytes for preamble,
and 1 byte for start frame delimiter, for a total of 20 bytes (160 bits) per packet
more than some non–E Series routers. This value therefore shows the total
bandwidth utilization on the interface, including both data and overhead.
To bridge unicast known-DA packets at line rate on both 2-Gbps ports of the
GE-2 line module or the GE-HDE module when paired with the GE-2 SFP I/O
module, the minimum packet size must be at least 144 bytes.
When installed in the ERX1440 router, the GE-2 module delivers full bandwidth
of 4 GB per line module (2 GB at the ingress and 2 GB at the egress) only when
installed in slot 2 or slot 4, and when the SRP-40G+ module is used in the
router. When installed in any other ERX1440 slot, the GE-2 module delivers a
maximum bandwidth of 2 GB per line module (1 GB maximum at the ingress
and 1 GB maximum at the egress). Therefore, of the maximum 24 possible
ports for the module in an ERX1440 chassis (that is, two ports in each of 12
slots), full bandwidth is delivered only on a maximum of four ports (those in
slots 2 and 4).
