1Smokeping_probes_CiscoRTTMonDNS(3) SmokePingSmokeping_probes_CiscoRTTMonDNS(3)
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6 Smokeping::probes::CiscoRTTMonDNS.pm - Probe for SmokePing
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9 *** Probes ***
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11 +CiscoRTTMonDNS
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13 forks = 5
14 offset = 50%
15 step = 300
16 timeout = 15
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18 # The following variables can be overridden in each target section
19 ioshost = RTTcommunity@Myrouter.foobar.com.au # mandatory
20 iosint = 10.33.22.11
21 name = www.foobar.com.au # mandatory
22 pings = 5
23 timeout = 15
24
25 # [...]
26
27 *** Targets ***
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29 probe = CiscoRTTMonDNS # if this should be the default probe
30
31 # [...]
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33 + mytarget
34 # probe = CiscoRTTMonDNS # if the default probe is something else
35 host = my.host
36 ioshost = RTTcommunity@Myrouter.foobar.com.au # mandatory
37 iosint = 10.33.22.11
38 name = www.foobar.com.au # mandatory
39 pings = 5
40 timeout = 15
41
43 A probe for smokeping, which uses the ciscoRttMon MIB functionality
44 ("Service Assurance Agent", "SAA") of Cisco IOS to time ( recursive,
45 type A) DNS queries to a DNS server.
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48 Supported probe-specific variables:
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50 forks
51 Run this many concurrent processes at maximum
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53 Example value: 5
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55 Default value: 5
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57 offset
58 If you run many probes concurrently you may want to prevent them
59 from hitting your network all at the same time. Using the probe-
60 specific offset parameter you can change the point in time when
61 each probe will be run. Offset is specified in % of total interval,
62 or alternatively as 'random', and the offset from the 'General'
63 section is used if nothing is specified here. Note that this does
64 NOT influence the rrds itself, it is just a matter of when data
65 acqusition is initiated. (This variable is only applicable if the
66 variable 'concurrentprobes' is set in the 'General' section.)
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68 Example value: 50%
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70 step
71 Duration of the base interval that this probe should use, if
72 different from the one specified in the 'Database' section. Note
73 that the step in the RRD files is fixed when they are originally
74 generated, and if you change the step parameter afterwards, you'll
75 have to delete the old RRD files or somehow convert them. (This
76 variable is only applicable if the variable 'concurrentprobes' is
77 set in the 'General' section.)
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79 Example value: 300
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81 timeout
82 How long a single 'ping' takes at maximum
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84 Example value: 15
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86 Default value: 5
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88 Supported target-specific variables:
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90 ioshost
91 The (mandatory) ioshost parameter specifies the Cisco router, which
92 will send the DNS requests, as well as the SNMP community string on
93 the router.
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95 Example value: RTTcommunity@Myrouter.foobar.com.au
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97 This setting is mandatory.
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99 iosint
100 The (optional) iosint parameter is the source address for the DNS
101 packets. This should be one of the active (!) IP addresses of the
102 router to get results. IOS looks up the target host address in the
103 forwarding table and then uses the interface(s) listed there to
104 send the DNS packets. By default IOS uses the (primary) IP address
105 on the sending interface as source address for packets originated
106 by the router.
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108 Example value: 10.33.22.11
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110 name
111 The (mandatory) name parameter is the DNS name to resolve.
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113 Example value: www.foobar.com.au
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115 This setting is mandatory.
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117 pings
118 How many pings should be sent to each target, if different from the
119 global value specified in the Database section. Note that the
120 number of pings in the RRD files is fixed when they are originally
121 generated, and if you change this parameter afterwards, you'll have
122 to delete the old RRD files or somehow convert them.
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124 Example value: 5
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126 timeout
127 How long a single RTTMonDNS 'ping' take at maximum plus 10 seconds
128 to spare. Since we control our own timeout the only purpose of this
129 is to not have us killed by the ping method from basefork.
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131 Example value: 15
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133 Default value: 15
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136 Joerg.Kummer at Roche.com
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139 host parameter
140 The host parameter specifies the DNS server, which the router will use.
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142 IOS VERSIONS
143 This probe only works with IOS 12.0(3)T or higher. It is recommended
144 to test it on less critical routers first.
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146 INSTALLATION
147 To install this probe copy ciscoRttMonMIB.pm to
148 ($SMOKEPINGINSTALLDIR)/lib/Smokeping and CiscoRTTMonDNS.pm to
149 ($SMOKEPINGINSTALLDIR)/lib/Smokeping/probes.
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151 The router(s) must be configured to allow read/write SNMP access.
152 Sufficient is:
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154 snmp-server community RTTCommunity RW
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156 If you want to be a bit more restrictive with SNMP write access to the
157 router, then consider configuring something like this
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159 access-list 2 permit 10.37.3.5
160 snmp-server view RttMon ciscoRttMonMIB included
161 snmp-server community RTTCommunity view RttMon RW 2
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163 The above configuration grants SNMP read-write only to 10.37.3.5 (the
164 smokeping host) and only to the ciscoRttMon MIB tree. The probe does
165 not need access to SNMP variables outside the RttMon tree.
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168 The probe does unnecessary DNS queries, i.e. more than configured in
169 the "pings" variable, because the RTTMon MIB only allows to set a total
170 time for all queries in one measurement run (one "life"). Currently the
171 probe sets the life duration to "pings"*5+3 seconds (5 secs is the
172 timeout value hardcoded into this probe).
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175 <http://oss.oetiker.ch/smokeping/>
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177 <http://www.switch.ch/misc/leinen/snmp/perl/>
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179 The best source for background info on SAA is Cisco's documentation on
180 <http://www.cisco.com> and the CISCO-RTTMON-MIB documentation, which is
181 available at:
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183 <ftp://ftp.cisco.com/pub/mibs/v2/CISCO-RTTMON-MIB.my>
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1872.7.3 2021-07-23Smokeping_probes_CiscoRTTMonDNS(3)