Commit:     8d4ef88b5df1afe097e38aef8cab2ed35ca141ea
Parent:     0cc120bea1d4ba3893a26c70d271e89f928b8a97
Author:     Satyam Sharma <[EMAIL PROTECTED]>
AuthorDate: Fri Aug 10 15:31:19 2007 -0700
Committer:  David S. Miller <[EMAIL PROTECTED]>
CommitDate: Wed Oct 10 16:48:04 2007 -0700

    [NET] netconsole: Add some useful tips to documentation
    Based upon initial work by Keiichi Kii <[EMAIL PROTECTED]>.
    Add some useful general-purpose tips.  Also suggest solution for the 
    problem of console loglevel set too low numerically (i.e.  for high priority
    messages only) on the sender.
    Signed-off-by: Satyam Sharma <[EMAIL PROTECTED]>
    Acked-by: Keiichi Kii <[EMAIL PROTECTED]>
    Acked-by: Matt Mackall <[EMAIL PROTECTED]>
    Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
    Signed-off-by: David S. Miller <[EMAIL PROTECTED]>
 Documentation/networking/netconsole.txt |   25 +++++++++++++++++++++++++
 1 files changed, 25 insertions(+), 0 deletions(-)

diff --git a/Documentation/networking/netconsole.txt 
index 1caa6c7..5962f45 100644
--- a/Documentation/networking/netconsole.txt
+++ b/Documentation/networking/netconsole.txt
@@ -44,11 +44,36 @@ WARNING: the default target ethernet setting uses the 
 ethernet address to send packets, which can cause increased load on
 other systems on the same ethernet segment.
+TIP: some LAN switches may be configured to suppress ethernet broadcasts
+so it is advised to explicitly specify the remote agents' MAC addresses
+from the config parameters passed to netconsole.
+TIP: to find out the MAC address of, say,, you may try using:
+ ping -c 1 ; /sbin/arp -n | grep
+TIP: in case the remote logging agent is on a separate LAN subnet than
+the sender, it is suggested to try specifying the MAC address of the
+default gateway (you may use /sbin/route -n to find it out) as the
+remote MAC address instead.
 NOTE: the network device (eth1 in the above case) can run any kind
 of other network traffic, netconsole is not intrusive. Netconsole
 might cause slight delays in other traffic if the volume of kernel
 messages is high, but should have no other impact.
+NOTE: if you find that the remote logging agent is not receiving or
+printing all messages from the sender, it is likely that you have set
+the "console_loglevel" parameter (on the sender) to only send high
+priority messages to the console. You can change this at runtime using:
+ dmesg -n 8
+or by specifying "debug" on the kernel command line at boot, to send
+all kernel messages to the console. A specific value for this parameter
+can also be set using the "loglevel" kernel boot option. See the
+dmesg(8) man page and Documentation/kernel-parameters.txt for details.
 Netconsole was designed to be as instantaneous as possible, to
 enable the logging of even the most critical kernel bugs. It works
 from IRQ contexts as well, and does not enable interrupts while
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