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by Guido Socher (homepage)
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A Hardware watchdog and shutdown button
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#!/bin/sh
PATH=/bin:/usr/bin:/usr/local/bin
export PATH
#
# Monitor the disk
# ----------------
# check if any of the partitions are more than 80% full.
# (crontab will automatically send an e-mail if this script
# produces some output)
df | egrep ' (8.%|9.%|100%) '
#
# Monitor the swap
# A server should normally be dimensioned such that it
# does not swap. Swap space should therefore be constant
# and limited.
# ----------------
# check if more than 6 Mb of swap are used
swpfree=`free | awk '/Swap:/{ print $3 }'`
if expr $swpfree \> 6000 > /dev/null ; then
echo "$0 warning! swap usage is now $swpfree"
echo " "
free
echo " "
ps auxw
fi
#
# Monitor the network
# -------------------
# your _own_ IP addr or hostname:
hostn="linuxbox.your.supercomputer"
#
if ping -w 5 -qn -c 1 $hostn > /dev/null ; then
# ok host is up
echo "0" > /etc/pingfail
else
# no answer count up the ping failures
if [ -r /etc/pingfail ]; then
pingfail=`cat /etc/pingfail`
else
# we do not handle the case where the
# pingfail file is missing
exit 0
fi
pingfail=`expr "$pingfail" "+" 1`
echo "$pingfail ping failures"
echo "$pingfail" > /etc/pingfail
if [ $pingfail -gt 10 ]; then
echo "more than 10 ping failures. System reboot..."
/sbin/shutdown -t2 -r now
fi
fi
# --- end of monitor script ---
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Name |
Dir |
Description |
| 1 |
8 |
CD |
input |
Carrier Detect |
| 2 |
3 |
RXD |
input |
Receive Data |
| 3 |
2 |
TXD |
output |
Transmit Data |
| 4 |
20 |
DTR |
output |
Data Terminal Ready |
| 5 |
7 |
GND |
-- |
System Ground |
| 6 |
6 |
DSR |
input |
Data Set Ready |
| 7 |
4 |
RTS |
output |
Request to Send |
| 8 |
5 |
CTS |
input |
Clear to Send |
| 9 |
22 |
RI |
input |
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2002-07-24, generated by lfparser version 2.25
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