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iPhone OS 3.0 Bluetooth tethering with Mac Book Pro
Here is a step by step guide to help you get online with your iPhone using OS 3.0.
- Go to this page: http://www.iphone-notes.de/mobileconfig/ It will send you an email. Download that email on you iPhone. It contains a profile to enable Tethering.
- Now go to your iPhone preferences, under Network you can enable tethering, activate it
- On your Mac Book Pro, go to the bluetooth preferences. Add your iPhone. I had to press "continue" on my Mac Book pro after accepting the pairing request on the iPhone. Waiting here resulted in an error.
- On you Mac Book Pro, connect to your iPhone using bluetooth
- Now on your Mac Book Pro, under Network Preferences, add a connection: "Bluetooth PAN".
You can now tether using your iPhone!
For tethering, an extra network interface is added, in my case "en5". To see what the IP-address of your connection is, open a Terminal and type:
ifconfig en5In my case I see that I am using a private class (192.168.20.0/24) IP address. That means that T-Mobile in the Netherlands is NAT-ing my connection. Not a problem, but connecting back to my laptop is not possible from the internet.
Convert a human readable date to epoch with a shell script on OpenBSD and Mac OS X
Dates can be quite challenging. Especially if you systematically want to use dates, for example to compare what date is older.
If you would like to convert this date into epoch, take these steps.
$ # The first step is to print the date.
$ echo "2009/05/25 18:34:30;"
2009/05/25 18:34:30;
$ # This step is to strip the /-es.
$ echo "2009/05/25 18:34:30;" | sed 's%/%%g'
20090525 18:34:30;
$ # This step removes the space
$ echo "2009/05/25 18:34:30;" | sed 's%/%%g;s% %%g'
2009052518:34:30;
$ # This step removes the trailing :30;.
$ echo "2009/05/25 18:34:30;" | sed 's%/%%g;s% %%g;s%:..;%%'
2009052518:34
$ # This step removes the :.
$ echo "2009/05/25 18:34:30;" | sed 's%/%%g;s% %%g;s%:..;%%;s%:%%g'
200905251834
$ # Finally feed that output to the "date" command.
$ date -j "+%s" $(echo "2009/05/25 18:34:30;" | sed 's%/%%g;s% %%g;s%:..;%%;s%:%%g')
1243269240On Mac OS X you'd have to use this command:
$ date -j -f date -j -f "%Y/%m/%d %T" "2009/10/15 04:58:06" +"%s"
1255575486Configure soekris as a OpenBSD wireless NAT router.
I use a Soekris device, bought mine for € 70,- with a wireless network interface. (wi0)
Besides that interface, this "machine" has two other ports; sis0 going to the modem and sis1 is not used, but any computer may be connected.
How difficult would it be to use this machine as a router using OpenBSD? Not difficult at all!
First install your Soekris with OpenBSD.
Now login and configure a few things.
# vi /etc/rc.conf.local
# Start NTP, it syncs time and requires very little maintenance.
ntpd_flags="-s"
# Start a DNS server.
named_flags=
# Clients should receive an IP-address. DHCP will only listen on sis1 and wi0, the network
# interfaces where computers will connect on. Don't start DHCP on your "modem-port".
dhcpd_flags="sis1 wi0"
# Enable Packet Filter.
pf=
# Here are the rules for PF.
pf_rules=/etc/pf.confConfigure named, the DNS server.
# cat /var/named/etc/named.conf
// $OpenBSD: named-simple.conf,v 1.9 2008/08/29 11:47:49 jakob Exp $
//
// Example file for a simple named configuration, processing both
// recursive and authoritative queries using one cache.
// Update this list to include only the networks for which you want
// to execute recursive queries. The default setting allows all hosts
// on any IPv4 networks for which the system has an interface, and
// the IPv6 localhost address.
//
acl clients {
localnets;
::1;
};
options {
version ""; // remove this to allow version queries
listen-on { any; };
listen-on-v6 { any; };
empty-zones-enable yes;
allow-recursion { clients; };
};
logging {
category lame-servers { null; };
};
// Standard zones
//
zone "." {
type hint;
file "etc/root.hint";
};
zone "localhost" {
type master;
file "standard/localhost";
allow-transfer { localhost; };
};
zone "127.in-addr.arpa" {
type master;
file "standard/loopback";
allow-transfer { localhost; };
};
zone "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa" {
type master;
file "standard/loopback6.arpa";
allow-transfer { localhost; };
};
zone "lan.meinit.nl" {
type master;
file "master/lan.meinit.nl";
};
zone "wifi.meinit.nl" {
type master;
file "master/wifi.meinit.nl";
};
zone "1.168.192.in-addr.arpa" {
type master;
file "master/1.168.192.in-addr.arpa";
};
zone "2.168.192.in-addr.arpa" {
type master;
file "master/2.168.192.in-addr.arpa";
};Now add all zones.
# cat lan.meinit.nl
$ORIGIN lan.meinit.nl.
$TTL 6h
@ IN SOA lan.meinit.nl. root.meinit.nl. (
1 ; serial
1h ; refresh
30m ; retry
7d ; expiration
1h ) ; minimum
NS soekris.lan.meinit.nl.
soekris A 192.168.1.1
32 A 192.168.1.32
33 A 192.168.1.33
34 A 192.168.1.34
35 A 192.168.1.35
36 A 192.168.1.36
37 A 192.168.1.37
38 A 192.168.1.38
39 A 192.168.1.39
40 A 192.168.1.40
41 A 192.168.1.41
42 A 192.168.1.42
43 A 192.168.1.43
44 A 192.168.1.44
45 A 192.168.1.45
46 A 192.168.1.46
47 A 192.168.1.47
48 A 192.168.1.48
49 A 192.168.1.49
50 A 192.168.1.50
51 A 192.168.1.51
52 A 192.168.1.52
53 A 192.168.1.53
54 A 192.168.1.54
55 A 192.168.1.55
56 A 192.168.1.56
57 A 192.168.1.57
58 A 192.168.1.58
59 A 192.168.1.59
60 A 192.168.1.60
61 A 192.168.1.61
62 A 192.168.1.62
63 A 192.168.1.63
64 A 192.168.1.64
65 A 192.168.1.65
66 A 192.168.1.66
67 A 192.168.1.67
68 A 192.168.1.68
69 A 192.168.1.69
70 A 192.168.1.70
71 A 192.168.1.71
72 A 192.168.1.72
73 A 192.168.1.73
74 A 192.168.1.74
75 A 192.168.1.75
76 A 192.168.1.76
77 A 192.168.1.77
78 A 192.168.1.78
79 A 192.168.1.79
80 A 192.168.1.80
81 A 192.168.1.81
82 A 192.168.1.82
83 A 192.168.1.83
84 A 192.168.1.84
85 A 192.168.1.85
86 A 192.168.1.86
87 A 192.168.1.87
88 A 192.168.1.88
89 A 192.168.1.89
90 A 192.168.1.90
91 A 192.168.1.91
92 A 192.168.1.92
93 A 192.168.1.93
94 A 192.168.1.94
95 A 192.168.1.95
96 A 192.168.1.96
97 A 192.168.1.97
98 A 192.168.1.98
99 A 192.168.1.99
100 A 192.168.1.100
101 A 192.168.1.101
102 A 192.168.1.102
103 A 192.168.1.103
104 A 192.168.1.104
105 A 192.168.1.105
106 A 192.168.1.106
107 A 192.168.1.107
108 A 192.168.1.108
109 A 192.168.1.109
110 A 192.168.1.110
111 A 192.168.1.111
112 A 192.168.1.112
113 A 192.168.1.113
114 A 192.168.1.114
115 A 192.168.1.115
116 A 192.168.1.116
117 A 192.168.1.117
118 A 192.168.1.118
119 A 192.168.1.119
120 A 192.168.1.120
121 A 192.168.1.121
122 A 192.168.1.122
123 A 192.168.1.123
124 A 192.168.1.124
125 A 192.168.1.125
126 A 192.168.1.126
127 A 192.168.1.127# cat wifi.meinit.nl
$ORIGIN wifi.meinit.nl.
$TTL 6h
@ IN SOA wifi.meinit.nl. root.meinit.nl. (
1 ; serial
1h ; refresh
30m ; retry
7d ; expiration
1h ) ; minimum
NS soekris.wifi.meinit.nl.
soekris A 192.168.2.1
32 A 192.168.2.32
33 A 192.168.2.33
34 A 192.168.2.34
35 A 192.168.2.35
36 A 192.168.2.36
37 A 192.168.2.37
38 A 192.168.2.38
39 A 192.168.2.39
40 A 192.168.2.40
41 A 192.168.2.41
42 A 192.168.2.42
43 A 192.168.2.43
44 A 192.168.2.44
45 A 192.168.2.45
46 A 192.168.2.46
47 A 192.168.2.47
48 A 192.168.2.48
49 A 192.168.2.49
50 A 192.168.2.50
51 A 192.168.2.51
52 A 192.168.2.52
53 A 192.168.2.53
54 A 192.168.2.54
55 A 192.168.2.55
56 A 192.168.2.56
57 A 192.168.2.57
58 A 192.168.2.58
59 A 192.168.2.59
60 A 192.168.2.60
61 A 192.168.2.61
62 A 192.168.2.62
63 A 192.168.2.63
64 A 192.168.2.64
65 A 192.168.2.65
66 A 192.168.2.66
67 A 192.168.2.67
68 A 192.168.2.68
69 A 192.168.2.69
70 A 192.168.2.70
71 A 192.168.2.71
72 A 192.168.2.72
73 A 192.168.2.73
74 A 192.168.2.74
75 A 192.168.2.75
76 A 192.168.2.76
77 A 192.168.2.77
78 A 192.168.2.78
79 A 192.168.2.79
80 A 192.168.2.80
81 A 192.168.2.81
82 A 192.168.2.82
83 A 192.168.2.83
84 A 192.168.2.84
85 A 192.168.2.85
86 A 192.168.2.86
87 A 192.168.2.87
88 A 192.168.2.88
89 A 192.168.2.89
90 A 192.168.2.90
91 A 192.168.2.91
92 A 192.168.2.92
93 A 192.168.2.93
94 A 192.168.2.94
95 A 192.168.2.95
96 A 192.168.2.96
97 A 192.168.2.97
98 A 192.168.2.98
99 A 192.168.2.99
100 A 192.168.2.100
101 A 192.168.2.101
102 A 192.168.2.102
103 A 192.168.2.103
104 A 192.168.2.104
105 A 192.168.2.105
106 A 192.168.2.106
107 A 192.168.2.107
108 A 192.168.2.108
109 A 192.168.2.109
110 A 192.168.2.110
111 A 192.168.2.111
112 A 192.168.2.112
113 A 192.168.2.113
114 A 192.168.2.114
115 A 192.168.2.115
116 A 192.168.2.116
117 A 192.168.2.117
118 A 192.168.2.118
119 A 192.168.2.119
120 A 192.168.2.120
121 A 192.168.2.121
122 A 192.168.2.122
123 A 192.168.2.123
124 A 192.168.2.124
125 A 192.168.2.125
126 A 192.168.2.126
127 A 192.168.2.127# cat 1.168.192.in-addr.arpa
$ORIGIN 1.168.192.in-addr.arpa.
$TTL 6h
@ IN SOA lan.home.meinit.nl. root.meinit.nl. (
1 ; serial
1h ; refresh
30m ; retry
7d ; expiration
1h ) ; minimum
NS soekris.lan.meinit.nl.
1 PTR soekris.lan.meinit.nl.
$GENERATE 32-127 $ PTR $.lan.meinit.nl.# cat 2.168.192.in-addr.arpa
$ORIGIN 2.168.192.in-addr.arpa.
$TTL 6h
@ IN SOA wifi.meinit.nl. root.meinit.nl. (
1 ; serial
1h ; refresh
30m ; retry
7d ; expiration
1h ) ; minimum
NS soekris.home.meinit.nl.
1 PTR soekris.wifi.meinit.nl.
$GENERATE 32-127 $ PTR $.wifi.meinit.nl.And setup the DHCP server.
# cat /etc/dhcpd.conf
subnet 192.168.1.0 netmask 255.255.255.0 {
option domain-name "lan.meinit.nl";
option domain-name-servers 192.168.1.1;
option routers 192.168.1.1;
range 192.168.1.32 192.168.1.127;
}
subnet 192.168.2.0 netmask 255.255.255.0 {
option domain-name "wifi.meinit.nl";
option domain-name-servers 192.168.2.1;
option routers 192.168.2.1;
range 192.168.2.32 192.168.2.127;
}Finally configure your PF in /etc/pf.conf:
# wan is the interface to which the modem is connected.
wan = sis0
# This is an extra interface, not in use right now, but you could connect a cable.
lan = sis1
# This is the (Prism 2) wireless network card. Clients will connect to this interface mostly.
wifi = wi0
scrub in all
nat on $wan from !($wan) to any -> ($wan)Now beter reboot to activate all changes. (Sure you could start every daemon by hand...)
Using Virtualbox on Mac OS X
Virtualbox is a open source virtualization tool that runs on many operating systems, including Mac OS X It's free, simple and it works, but you'll need to be aware of how to use it. Here are my experiences with different settings.
The default network driver makes an airport interface (en1) on Mac OS X unstable. So; either map the virtual interface to a wired network interface (en0) or use another driver. The Intel PRO/1000 MT Desktop (8254OEM) works fine for me, the PCnet-FAST II (Am78C973) does not work well for me.
For FreeBSD guest operating systems, the default IDE disk causes timeouts. Better use a SATA emulation, IDE emulation causes errors during the install.
Have fun using Virtualbox, after all, its free!
Update Soekris bios firmware from your Apple Mac OS X machine
When you are using a Soekris, a new bios is published every now and then. Because I had to search-copy-try-paste quite some time to get my Apple Mac OS X to upload the most recent Soekris (net4521) bios.
Here is what you need:
- Hardware: a USB-to-serial cable. I used a IOGear CUG232A.
- Software: a driver for that USB-to-serial cable.
- Firmware: A recent firmware for your soekris.
- Software: lsr. from the lrzsz project.
I downloaded b4501_133.bin.
The driver for the IOGear USB-to-serial cable creates a device called /dev/tty.PL2303-00002006. The Soekris will most likely run on 19200 bps. If your Soekris spits out unreadable text, try a speed like 9600. If you are able to access the Soekris bios, you can always change the serial speed using "set ConSpeed=19200" for example.
# cu -l /dev/tty.PL2303-00002006 -s 19200
POST: 012345689bcefghipsajklnopqr,,,tvwxy
comBIOS ver. 1.33 20080103 Copyright (C) 2000-2007 Soekris Engineering.
net45xx
0064 Mbyte Memory CPU Elan SC520 133 Mhz
Pri Mas LEXAR ATA FLASH LBA Xlt 999-32-63 1007 Mbyte
Slot Vend Dev ClassRev Cmd Stat CL LT HT Base1 Base2 Int
-------------------------------------------------------------------
0:00:0 1022 3000 06000000 0006 2280 00 00 00 00000000 00000000
0:17:0 104C AC51 06070000 0107 0210 10 3F 82 A0000000 020000A0 10
0:17:1 104C AC51 06070000 0107 0210 10 3F 82 A0001000 020000A0 10
0:18:0 100B 0020 02000000 0107 0290 00 3F 00 0000E101 A0002000 11
0:19:0 100B 0020 02000000 0107 0290 00 3F 00 0000E201 A0003000 05
1 Seconds to automatic boot. Press Ctrl-P for entering Monitor.
> download -
Start sending file using XMODEM/CRC protocol.
~+./lsz -X b4501_133.bin
Sending b4501_133.bin, 608 blocks: Give your local XMODEM receive command now.
Bytes Sent: 77824 BPS:1745
Transfer complete
File downloaded succesfully, size 608 Blocks.
> flashupdate
Updating BIOS Flash ,,,,,,,,,,,,..,,,,.. Done.
> rebootGood, you are done!
Install your Soekris (or any other machine) with OpenBSD using OpenBSD
To install OpenBSD on your Soekris machine, (or any other machine) take these steps to create an OpenBSD installation server. This instruction help you setup a DHCP, TFTP and HTTP server required for a network installation of OpenBSD.
This setup creates an autonomous install server, that can be disconnected from the internet. During the setup this machine is connected to the internet to install all required software.
First; install an OpenBSD machine. This may either be virtual or physical. Just install the default set of software and make sure it's connected to the internet. (It does not matter if you are using DHCP or a static IP configuration.)
This instruction is based on OpenBSD 4.5, but will likely work for future releases.
Install a DHCP server.
# export PKG_PATH=http://mirror.roothell.org/pub/OpenBSD/4.5/packages/i386/
# pkg_add isc-dhcp-server
isc-dhcp-server-3.1.1: completeConfigure the DHCP server. This step is very dependent of your network configuration, so don't just copy paste everything, but try to understand (using man pages) what's configured.
My /etc/dhcpd.conf looks like this now:
option domain-name "home.meinit.nl";
option domain-name-servers 192.168.1.1;
subnet 192.168.1.0 netmask 255.255.255.0 {
range 192.168.1.32 192.168.1.127;
host pxe-client {
hardware ethernet 02:03:04:05:06:07;
filename "pxeboot";
next-server 192.168.1.1;
}
}Be aware; the "hardware ethernet" address mentioned above is not correct. It needs to be set to what the MAC address is of the machine you would like to install.
Make sure it start by modifying /etc/rc.conf.local, like this:
# echo "dhcpd_flags=" >> /etc/rc.conf.localEnable the TFTP server in /etc/inetd.conf: (It's installed by default on an OpenBSD installation!)
tftp dgram udp wait root /usr/libexec/tftpd tftpd -s /tftpbootCreate some directories and restart inetd:
# pkill -HUP inetdNow get the kernel that is being used when booting over the network and retreive the PXE boot code.
# cd /tftpboot
# ftp http://mirror.roothell.org/pub/OpenBSD/4.5/i386/bsd.rd
Trying 88.198.153.75...
Requesting http://mirror.roothell.org/pub/OpenBSD/4.5/i386/bsd
100% |*******************************************************************************| 5461 KB 00:06
Successfully retrieved file.
# echo "set tty com0
stty com0 19200
boot bsd.rd" > etc/boot.conf
# ftp http://mirror.roothell.org/pub/OpenBSD/4.5/i386/pxeboot
Trying 88.198.153.75...
Requesting http://mirror.roothell.org/pub/OpenBSD/4.5/i386/pxeboot
100% |*******************************************************************************| 53276 00:00
Successfully retrieved file.Enable a HTTP server.
# echo "httpd_flags=" >> /etc/rc.conf.localNow get all required software sets you'd like to offer.
# ftp http://mirror.roothell.org/pub/OpenBSD/4.5/i386/index.txt
Trying 88.198.153.75...
Requesting http://mirror.roothell.org/pub/OpenBSD/4.5/i386/index.txt
100% |*******************************************************************************| 266 00:00
Successfully retrieved file.
# cat index.txt | grep -v '.iso' | tee index.txt | while read file ; do
> ftp http://mirror.roothell.org/pub/OpenBSD/4.5/i386/"$file"
> done
100% |********************************************************************************| 106 KB 00:00
100% |********************************************************************************| 22356 00:00
100% |********************************************************************************| 1022 00:00
100% |********************************************************************************| 46941 KB 00:27
100% |********************************************************************************| 6539 KB 00:02
100% |********************************************************************************| 6558 KB 00:03
100% |********************************************************************************| 5461 KB 00:02
100% |********************************************************************************| 44724 00:00
100% |********************************************************************************| 2048 00:00
100% |********************************************************************************| 87874 KB 00:59
100% |********************************************************************************| 501 KB 00:00
100% |********************************************************************************| 1440 KB 00:00
100% |********************************************************************************| 1440 KB 00:00
100% |********************************************************************************| 1440 KB 00:00
100% |********************************************************************************| 2555 KB 00:00
100% |********************************************************************************| 8032 KB 00:03
100% |********************************************************************************| 2866 KB 00:02
100% |********************************************************************************| 53276 00:00
100% |********************************************************************************| 9761 KB 00:07
100% |********************************************************************************| 75214 00:01
100% |********************************************************************************| 34745 KB 00:26
100% |********************************************************************************| 19478 KB 00:11
100% |********************************************************************************| 2698 KB 00:06 Now that everything is ready, reconfigure your network to use a static IP which is usable in the network you are planning this installation server.
NOTA BENE: you have enabled a DHCP server, if your network already uses a DHCP server, clients might get an IP address from your DHCP server, which is likely incorrect and/or conflicting with the exiting DHCP server. Normally you'd like to use one DHCP server per network.
# echo "inet 192.168.1.1 255.255.255.0 192.168.1.255" > /etc/hostname.em0
# echo "lookup file" > /etc/resolv.conf
# rebootNow in the freshly installed client, modify/create /etc/boot.conf with this content:
set tty com0
stty com0 19200The Soekris uses these setting to be able to access the serial console.
Okay, after your install server has been rebooted, go and boot an uninstalled client.
For soekris users; connect your console cable, see the machine boot.
You will see that it's first getting the pxeboot code, then the kernel (bsd). When the kernel has booted, select your bootservers IP address to install software from and enter "/" at the server directory question.
Add a permanent static route to Mac OS X
As a reminder for myself, but likely useful for you! If you are in a situation where you'd like to add a static route to you Mac OS X machine, you could issue:
$ sudo route add 10.0.0.0/8 192.168.1.1This commands tells the TCP/IP stack to sent traffic with the destination 10.*.*.* via 192.168.1.1. But, this command is only active after issuing it and before the next reboot. To "save" this command, make it permanent, you can take these simple steps.
$ sudo mkdir /Library/StartupItems/AddRoute
# cd /Library/StartupItems/AddRoute
$ echo "{
Description = \"Add static routing tables\";
Provides = (\"AddRoutes\");
Requires = (\"Network\");
OrderPreference = \"None\";
}" > StartupParameters.plist
$ echo "#!/bin/sh
# Set up static routing tables
# Roark Holz, Thursday, April 6, 2006
. /etc/rc.common
StartService ()
{
ConsoleMessage "Adding Static Routing Tables"
sudo route add 10.0.0.0/8 192.168.200.15
}
StopService ()
{
return 0
}
RestartService ()
{
return 0
}
RunService "$1"" > AddRoutes
$ sudo chmod 755 AddRoutesNow you should be prepared. After a reboot, the route will be visible. (netstat -rnf inet)
Nagios check for Centreon to create CPU graphs for Linux
Centreon is a great front-end for Nagios, the well known monitoring tool.
Nagios only performs "up" and "down" checks, Centreon adds performance graph capabilities.
Centreon comes with many checks to measure values, like traffic on eth0, a ping response time check, an ntp check and so on. Many checks are based on SNMP, so for Linux machines net-snmp should be installed.
What Centreon is missing, is an SNMP check that reports CPU usage and graphs the information. Here is a shell script to get the values for a specified host and return the CPU-idle percentage, CPU-system percentage and CPU-user percentage.
The script depends on a binary snmpget found in the package net-snmp-utils. Install it on the Nagios pollers that perform this check.
This script implements Performance Data as described by Nagios, which is very short means that besides outputting readable data, it also outputs performance data after the pipe ("|") mark, separated by a comma.
The script has been designed to incorporate all described requirements by Nagios plugins.
#!/bin/sh
# Nagios plugin to report CPU usage on Linux boxes.
usage() {
# This function is called when a user enters impossible values.
echo "Usage: $0 -H HOSTADDRESS [-C COMMUNITY] [-w WARNING] [-c CRITICAL] [-v VERSION]"
echo
echo " -H HOSTADDRESS"
echo " The host to check, either IP address or a resolvable hostname."
echo " -w WARNING"
echo " The percentage of cpu-idle to start warning, defaults to 15."
echo " -c CRITICAL"
echo " The percentage op cpu-idle to reflect a critical state, defaults to 5."
echo " -C COMMUNITY"
echo " The SNMP community to use, defaults to public."
echo " -v VERSION"
echo " The SNMTP version to use, defaults to 2c."
exit 3
}
readargs() {
# This function reads what options and arguments were given on the
# command line.
while [ "$#" -gt 0 ] ; do
case "$1" in
-H)
if [ "$2" ] ; then
host="$2"
shift ; shift
else
echo "Missing a value for $1."
echo
shift
usage
fi
;;
-w)
if [ "$2" ] ; then
warning="$2"
shift ; shift
else
echo "Missing a value for $1."
echo
shift
usage
fi
;;
-c)
if [ "$2" ] ; then
critical="$2"
shift ; shift
else
echo "Missing a value for $1."
echo
shift
usage
fi
;;
-C)
if [ "$2" ] ; then
community="$2"
shift ; shift
else
echo "Missing a value for $1."
echo
shift
usage
fi
;;
-v)
if [ "$2" ] ; then
version="$2"
shift ; shift
else
echo "Missing a value for $1."
echo
shift
usage
fi
;;
*)
echo "Unknown option $1."
echo
shift
usage
;;
esac
done
}
setvariables() {
# Here is a function to set some default values.
cpurawidle="UCD-SNMP-MIB::ssCpuRawIdle.0"
cpurawuser="UCD-SNMP-MIB::ssCpuRawUser.0"
cpurawsystem="UCD-SNMP-MIB::ssCpuRawSystem.0"
if [ ! "$warning" ] ; then warning="15" ; fi
if [ ! "$critical" ] ; then critical="5" ; fi
tmpdir="/tmp/nagios"
}
checkvariables() {
# This function checks if all collected input is correct.
if [ ! "$host" ] ; then
echo "Please specify a hostname or IP address."
echo
usage
fi
if [ "$warning" -lt "$critical" ] ; then
echo "Critical may not be higher than warning. Please modify your critical an warning values."
echo
usage
fi
if [ ! "$community" ] ; then
# The public community is used when a user did not enter a community.
community="public"
fi
if [ ! "$version" ] ; then
# Version 2c is used when a user did not enter a version.
version="2c"
fi
if [ ! -d "$tmpdir" ] ; then
mkdir "$tmpdir"
if [ $? -gt 0 ] ; then
echo "Unknown cannot create $tmpdir!"
exit 3
fi
fi
}
getandprintresults() {
# First, get all values in one snmpget session. I think this is lighter for
# the machine that is queried compared to three separated snmpgets.
snmpget -c "$community" -v "$version" -t 3 "$host" "$cpurawidle" "$cpurawuser" "$cpurawsystem" | while read mib equals type digit ; do
case "$mib" in
# This output is returned for the cpuidle value.
UCD-SNMP-MIB::ssCpuRawIdle.0)
cpuidlevalue="$digit"
;;
# This output is returned for the cpuuser value.
UCD-SNMP-MIB::ssCpuRawUser.0)
cpuuservalue="$digit"
;;
# This output is returned for the cpusystem value.
UCD-SNMP-MIB::ssCpuRawSystem.0)
cpusystemvalue="$digit"
if [ -f "$tmpdir"/"$host".cpuidle ] ; then
cpuidlediff=$(($cpuidlevalue - $(cat "$tmpdir"/"$host".cpuidle)))
fi
echo "$cpuidlevalue" > "$tmpdir"/"$host".cpuidle
if [ -f "$tmpdir"/"$host".cpuuser ] ; then
cpuuserdiff=$(($cpuuservalue - $(cat "$tmpdir"/"$host".cpuuser)))
fi
echo "$cpuuservalue" > "$tmpdir"/"$host".cpuuser
if [ ! -f "$tmpdir"/"$host".cpusystem ] ; then
echo "$cpusystemvalue" > "$tmpdir"/"$host".cpusystem
echo "First run, gathering data."
exit 3
else
cpusystemdiff=$(($cpusystemvalue - $(cat "$tmpdir"/"$host".cpusystem)))
echo "$cpusystemvalue" > "$tmpdir"/"$host".cpusystem
fi
# Add all differences, so a calculation of the percentage can be made later.
allcpu=$(($cpuidlediff + $cpuuserdiff + $cpusystemdiff))
# Now calculate how many percent each value represents.
cpuidlevalue=$((($cpuidlediff*100)/$allcpu))
cpuuservalue=$((($cpuuserdiff*100)/$allcpu))
cpusystemvalue=$((($cpusystemdiff*100)/$allcpu))
# Now see if any of these percentages is over a threshold.
if [ "$cpuidlevalue" -lt "$critical" ] ; then
# First see if it's in a critical state.
echo "CPU CRITICAL idle value: $cpuidlevalue%|cpuidle=$cpuidlevalue% cpuuservalue=$cpuuservalue% cpusystemvalue=$cpusystemvalue%"
exit 2
elif [ "$cpuidlevalue" -lt "$warning" ] ; then
# Now see if warning applies.
echo "CPU WARNING idle value: $cpuidlevalue%|cpuidle=$cpuidlevalue% cpuuservalue=$cpuuservalue% cpusystemvalue=$cpusystemvalue%"
exit 1
else
# If neither critical, nor warning apply, it must be OK!
echo "CPU OK idle value: $cpuidlevalue%|cpuidle=$cpuidlevalue% cpuuservalue=$cpuuservalue% cpusystemvalue=$cpusystemvalue%"
exit 0
fi
;;
esac
done
}
# The calls to the different functions.
readargs "$@"
setvariables
checkvariables
getandprintresultsDon't forget to chmod (755) the script on the Poller(s).
Now go into the Centreon web front end and add a command at:
Configuration - Commands - Add.
I named the check "check_cpu" where the command line is:
$USER1$/check_snmp_cpu -H $HOSTADDRESS$ -C $ARG1$Bind this check to a service template and bind a hostgroup to the service template. Remember Centreon does not use $USER2$, but $_HOSTSNMPCOMMUNITY$.
Pasting shell scripts from Microsoft Word into Putty
As a Linux/UNIX engineer you will have to cope with the strange behaviour of Microsofts products. Microsoft Word replaces a simple double quote (") for an angled quote. Now when you paste that code into Putty, your (angled) quotes are replaced for dots.
To correct this behaviour open Microsoft Word, click Tools then Autocorrection options and on the unselect Smart Quotes. (You may want to disable other "handy" features as well.
Finally, I am able to paste documented code into Putty!
Simple AWK script to show filesystems that are almost full
Here is a simple oneliner to show filesystems that are nearly full:
df -k | awk '$4 > 85 {print $7,$4}'What it does;
- df -k - This displays the filesystems and how full they are.
- awk '$4 > 85 {print $7,$4}' - This prints the 7th and 4th column, when the 4th column is greater than 85.
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| References | Red Hat Certified Architect | By Robert de Bock | Robert de Bock |
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| By Nelson Manning | robert@meinit.nl |
