- Memory allocation failures have been observed on Linux systems with 64 MB
- of RAM or less that are running Jumbo Frames. If you are using Jumbo
- Frames, your system may require more than the advertised minimum
- requirement of 64 MB of system memory.
-
- Performance Degradation with Jumbo Frames
- -----------------------------------------
-
- Degradation in throughput performance may be observed in some Jumbo frames
- environments. If this is observed, increasing the application's socket
- buffer size and/or increasing the /proc/sys/net/ipv4/tcp_*mem entry values
- may help. See the specific application manual and
- /usr/src/linux*/Documentation/
- networking/ip-sysctl.txt for more details.
-
- Jumbo frames on Foundry BigIron 8000 switch
- -------------------------------------------
- There is a known issue using Jumbo frames when connected to a Foundry
- BigIron 8000 switch. This is a 3rd party limitation. If you experience
- loss of packets, lower the MTU size.
-
- Multiple Interfaces on Same Ethernet Broadcast Network
- ------------------------------------------------------
-
- Due to the default ARP behavior on Linux, it is not possible to have
- one system on two IP networks in the same Ethernet broadcast domain
- (non-partitioned switch) behave as expected. All Ethernet interfaces
- will respond to IP traffic for any IP address assigned to the system.
- This results in unbalanced receive traffic.
-
- If you have multiple interfaces in a server, either turn on ARP
- filtering by entering:
-
- echo 1 > /proc/sys/net/ipv4/conf/all/arp_filter
- (this only works if your kernel's version is higher than 2.4.5),
-
- NOTE: This setting is not saved across reboots. The configuration
- change can be made permanent by adding the line:
- net.ipv4.conf.all.arp_filter = 1
- to the file /etc/sysctl.conf
-
- or,
-
- install the interfaces in separate broadcast domains (either in
- different switches or in a switch partitioned to VLANs).
-
- 82541/82547 can't link or are slow to link with some link partners
- -----------------------------------------------------------------
-
- There is a known compatibility issue with 82541/82547 and some
- low-end switches where the link will not be established, or will
- be slow to establish. In particular, these switches are known to
- be incompatible with 82541/82547:
-
- Planex FXG-08TE
- I-O Data ETG-SH8
-
- To workaround this issue, the driver can be compiled with an override
- of the PHY's master/slave setting. Forcing master or forcing slave
- mode will improve time-to-link.
-
- # make EXTRA_CFLAGS=-DE1000_MASTER_SLAVE=<n>
-
- Where <n> is:
-
- 0 = Hardware default
- 1 = Master mode
- 2 = Slave mode
- 3 = Auto master/slave
-
- Disable rx flow control with ethtool
- ------------------------------------
-
- In order to disable receive flow control using ethtool, you must turn
- off auto-negotiation on the same command line.
-
- For example:
-
- ethtool -A eth? autoneg off rx off