LO(4) BSD Kernel Interfaces Manual LO(4)NAME
lo -- software loopback network interface
SYNOPSIS
device loop
DESCRIPTION
The loop interface is a software loopback mechanism which may be used for performance analysis, software testing, and/or local communication.
As with other network interfaces, the loopback interface must have network addresses assigned for each address family with which it is to be
used. These addresses may be set or changed with the SIOCSIFADDR ioctl(2). The loopback interface should be the last interface configured,
as protocols may use the order of configuration as an indication of priority. The loopback should never be configured first unless no hard-
ware interfaces exist.
If the transmit checksum offload capability flag is enabled on a loopback interface, checksums will not be generated by IP, UDP, or TCP for
packets sent on the interface.
If the receive checksum offload capability flag is enabled on a loopback interface, checksums will not be validated by IP, UDP, or TCP for
packets received on the interface.
By default, both receive and transmit checksum flags will be enabled, in order to avoid the overhead of checksumming for local communication
where data corruption is unlikely. If transmit checksum generation is disabled, then validation should also be disabled in order to avoid
packets being dropped due to invalid checksums.
DIAGNOSTICS
lo%d: can't handle af%d. The interface was handed a message with addresses formatted in an unsuitable address family; the packet was
dropped.
SEE ALSO inet(4), intro(4)HISTORY
The lo device appeared in 4.2BSD. The current checksum generation and validation avoidance policy appeared in FreeBSD 8.0.
BSD March 15, 2009 BSD
Check Out this Related Man Page
LO(4) BSD Kernel Interfaces Manual LO(4)NAME
lo -- software loopback network interface
SYNOPSIS
device loop
DESCRIPTION
The loop interface is a software loopback mechanism which may be used for performance analysis, software testing, and/or local communication.
As with other network interfaces, the loopback interface must have network addresses assigned for each address family with which it is to be
used. These addresses may be set or changed with the SIOCSIFADDR ioctl(2). The loopback interface should be the last interface configured,
as protocols may use the order of configuration as an indication of priority. The loopback should never be configured first unless no hard-
ware interfaces exist.
If the transmit checksum offload capability flag is enabled on a loopback interface, checksums will not be generated by IP, UDP, or TCP for
packets sent on the interface.
If the receive checksum offload capability flag is enabled on a loopback interface, checksums will not be validated by IP, UDP, or TCP for
packets received on the interface.
By default, both receive and transmit checksum flags will be enabled, in order to avoid the overhead of checksumming for local communication
where data corruption is unlikely. If transmit checksum generation is disabled, then validation should also be disabled in order to avoid
packets being dropped due to invalid checksums.
DIAGNOSTICS
lo%d: can't handle af%d. The interface was handed a message with addresses formatted in an unsuitable address family; the packet was
dropped.
SEE ALSO inet(4), intro(4)HISTORY
The lo device appeared in 4.2BSD. The current checksum generation and validation avoidance policy appeared in FreeBSD 8.0.
BSD March 15, 2009 BSD
I'm using ethereal to analyse my network from my pc.
There're too many TCP Bad checksum
1. between my PC and unix servers (checksum: 0x6660 )
2. between my PC and other servers (windows, novell) checksum: 0x6644 )
There're too many NBNS and BOOTP/DHCP Malformed Packet(Exception occured) ... (0 Replies)
Hi Community,
Does anyone know how Disabling checksum offload on Solaris10?
Please help me, this issue is very urgent
Thank you
Have a nice day (3 Replies)
Hi,
could any one tell is there any test-suite or any idea How to do data corruption validation testing, means there is no any data corruption ?
Regards
Manish (1 Reply)