12-07-2005
Found this....
Quote:
Duplicated Incoming Packets
It is not uncommon to observe a short burst of duplicated traffic when the bonding device is first used, or after it has been idle for some period of time. This is most easily observed by issuing a "ping" to some other host on the network, and noticing that the output from ping flags duplicates (typically one per slave).
For example, on a bond in active-backup mode with five slaves all connected to one switch, the output may appear as follows:
# ping -n 10.0.4.2
PING 10.0.4.2 (10.0.4.2) from 10.0.3.10 : 56(84) bytes of data.
64 bytes from 10.0.4.2: icmp_seq=1 ttl=64 time=13.7 ms
64 bytes from 10.0.4.2: icmp_seq=1 ttl=64 time=13.8 ms (DUP!)
64 bytes from 10.0.4.2: icmp_seq=1 ttl=64 time=13.8 ms (DUP!)
64 bytes from 10.0.4.2: icmp_seq=1 ttl=64 time=13.8 ms (DUP!)
64 bytes from 10.0.4.2: icmp_seq=1 ttl=64 time=13.8 ms (DUP!)
64 bytes from 10.0.4.2: icmp_seq=2 ttl=64 time=0.216 ms
64 bytes from 10.0.4.2: icmp_seq=3 ttl=64 time=0.267 ms
64 bytes from 10.0.4.2: icmp_seq=4 ttl=64 time=0.222 ms
This is not due to an error in the bonding driver, rather, it is a side effect of how many switches update their MAC forwarding tables. Initially, the switch does not associate the MAC address in the packet with a particular switch port, and so it may send the traffic to all ports until its MAC forwarding table is updated. Since the interfaces attached to the bond may occupy multiple ports on a single switch, when the switch (temporarily) floods the traffic to all ports, the bond device receives multiple copies of the same packet (one per slave device).
The duplicated packet behavior is switch dependent, some switches exhibit this, and some do not. On switches that display this behavior, it can be induced by clearing the MAC forwarding table (on most Cisco switches, the privileged command "clear mac address-table dynamic" will accomplish this).
http://linux-net.osdl.org/index.php/Bonding
Cheers
ZB
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LEARN ABOUT DEBIAN
nischttl
nischttl(1) User Commands nischttl(1)
NAME
nischttl - change the time to live value of a NIS+ object
SYNOPSIS
nischttl [-AfLP] time name...
DESCRIPTION
nischttl changes the time to live value (ttl) of the NIS+ objects or entries specified by name to time. Entries are specified using indexed
names (see nismatch(1)).
The time to live value is used by object caches to expire objects within their cache. When an object is read into the cache, this value is
added to the current time in seconds yielding the time when the cached object would expire. The object may be returned from the cache until
the current time is earlier than the calculated expiration time. When the expiration time has been reached, the object will be flushed
from the cache.
The time to live time may be specified in seconds or in days, hours, minutes, seconds format. The latter format uses a suffix letter of d,
h, m, or s to identify the units of time. See the examples below for usage.
The command will fail if the master NIS+ server is not running.
Setting a high ttl value allows objects to stay persistent in caches for a longer period of time and can improve performance. However,
when an object changes, in the worst case, the number of seconds in this attribute must pass before that change is visible to all clients.
Setting a ttl value of 0 means that the object should not be cached at all.
A high ttl value is a week, a low value is less than a minute. Password entries should have ttl values of about 12 hours (easily allows
one password change per day), entries in the RPC table can have ttl values of several weeks (this information is effectively unchanging).
Only directory and group objects are cached in this implementation.
OPTIONS
The following options are supported:
-A Modify all tables in the concatenation path that match the search criterion specified in name. This option implies the -P switch.
-f Force the operation and fail silently if it does not succeed.
-L Follow links and change the time to live of the linked object or entries rather than the time to live of the link itself.
-P Follow the concatenation path within a named table. This option only makes sense when either name is an indexed name or the -L
switch is also specified and the named object is a link pointing to entries.
EXAMPLES
Example 1: Changing the ttl of an Object
The following example shows how to change the ttl of an object using the seconds format and the days, hours, minutes, seconds format. The
ttl of the second object is set to 1 day and 12 hours.
example% nischttl 184000 object
example% nischttl 1d12h object
Example 2: Changing the ttl for a password Entry
This example shows how to change the ttl for a password entry.
example% nischttl 1h30m '[uid=99],passwd.org_dir'
Example 3: Changing the ttl of Entries Pointed to by a Link
The next two examples change the ttl of the object or entries pointed to by a link, and the ttl of all entries in the hobbies table.
example% nischttl -L 12h linkname
example% nischttl 3600 '[],hobbies'
ENVIRONMENT VARIABLES
NIS_PATH If this variable is set, and the NIS+ name is not fully qualified, each directory specified will be searched until
the object is found. See nisdefaults(1).
EXIT STATUS
The following exit values are returned:
0 Successful operation.
1 Operation failed.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWnisu |
+-----------------------------+-----------------------------+
SEE ALSO
nis+(1), nischgrp(1), nischmod(1), nischown(1), nisdefaults(1), nismatch(1), nis_objects(3NSL), attributes(5)
NOTES
NIS+ might not be supported in future releases of the SolarisTM Operating Environment. Tools to aid the migration from NIS+ to LDAP are
available in the Solaris 9 operating environment. For more information, visit http://www.sun.com/directory/nisplus/transition.html.
SunOS 5.10 10 Dec 2001 nischttl(1)