2 The software in this package is distributed under the GNU General
3 Public License version 2 (with a special exception described below).
5 A copy of GNU General Public License (GPL) is included in this distribution,
6 in the file COPYING.GPL.
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9 or inline functions from this file, or you compile this file and link it
10 with other works to produce a work based on this file, this file
11 does not by itself cause the resulting work to be covered
12 by the GNU General Public License.
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15 in accordance with section (3) of the GNU General Public License.
17 This exception does not invalidate any other reasons why a work based
18 on this file might be covered by the GNU General Public License.
20 #include "host/pingscheduler.h"
25 #include <boost/bind.hpp>
26 #include <boost/foreach.hpp>
28 #include <logfunc.hpp>
30 #include "boost_assert_handler.h"
31 #include "host/pingerfactory.h"
32 #include "dns/dnsmaster.h"
33 #include "icmp/icmppinger.h"
34 #include "link/linkstatus.h"
37 using boost::asio::io_service;
39 using boost::date_time::time_resolution_traits_adapted64_impl;
40 using boost::posix_time::microsec_clock;
41 using boost::posix_time::ptime;
42 using boost::posix_time::seconds;
43 using boost::shared_ptr;
44 using I2n::Logger::GlobalLogger;
46 //-----------------------------------------------------------------------------
48 //-----------------------------------------------------------------------------
51 * @brief Parameterized constructor.
53 * @param io_serv The one @c io_serv object that controls async processing
54 * @param network_interface The name of the network interface sending the pings.
55 * @param destination_address The remote address to ping.
56 * @param destination_port The remote port to ping.
57 * @param ping_protocol_list A list of protocols to use.
58 * @param ping_interval_in_sec Amount of time between each ping.
59 * @param ping_fail_percentage_limit Maximum amount of pings that can fail.
60 * @param link_analyzer The object to monitor the link status.
61 * @param first_delay Delay in seconds from start_pinging to first ping attempt
63 PingScheduler::PingScheduler(
64 const IoServiceItem io_serv,
65 const string &network_interface,
66 const string &destination_address,
67 const uint16_t destination_port,
68 const PingProtocolList &ping_protocol_list,
69 const long ping_interval_in_sec,
70 const int ping_fail_percentage_limit,
71 const int ping_reply_timeout,
72 LinkStatusItem link_analyzer,
77 NetworkInterfaceName( network_interface ),
78 DestinationAddress( destination_address ),
79 DestinationPort( destination_port ),
80 Protocols( ping_protocol_list ),
82 PingIntervalInSec( ping_interval_in_sec ),
83 FirstDelay( first_delay ),
84 NextPingTimer( *io_serv ),
85 TimeSentLastPing( microsec_clock::universal_time() ),
86 PingReplyTimeout( ping_reply_timeout ),
87 HostAnalyzer( destination_address, ping_fail_percentage_limit,
93 ContinueOnOutdatedIps( false )
95 BOOST_ASSERT( !network_interface.empty() );
96 BOOST_ASSERT( !destination_address.empty() );
97 BOOST_ASSERT( ( 0 < destination_port ) &&
98 ( destination_port < numeric_limits<uint16_t>::max() ) );
99 BOOST_ASSERT( 0 < ping_interval_in_sec );
100 BOOST_ASSERT( (0 <= ping_fail_percentage_limit) &&
101 ( ping_fail_percentage_limit <= 100) );
105 init_ping_protocol();
111 PingScheduler::~PingScheduler()
115 void PingScheduler::stop_pinging()
117 // stop pinger and resolver
118 GlobalLogger.debug() << LogPrefix << "scheduler: stop pinging";
119 Ping->stop_pinging();
120 cancel_resolve(true);
122 // now cancel the own timer in case that pinger cancelation called callback
123 GlobalLogger.debug() << LogPrefix << "scheduler: cancel timer";
124 NextPingTimer.cancel();
128 * @brief Start into infinite loop of calls to ping
130 * Does not start yet but set NextPingTimer (possibly to 0), so action starts
131 * when io_service is started
133 void PingScheduler::start_pinging()
135 if ( FirstDelay > 0 )
136 GlobalLogger.info() << LogPrefix << "Delaying first ping by "
137 << FirstDelay << "s";
139 GlobalLogger.info() << LogPrefix << "Schedule ping as soon as possible";
141 (void) NextPingTimer.expires_from_now( seconds( FirstDelay ) );
142 NextPingTimer.async_wait( bind( &PingScheduler::ping, this,
143 boost::asio::placeholders::error ) );
148 * @brief call Ping::ping and schedule a call to ping_done_handler when finished
150 void PingScheduler::ping(const boost::system::error_code &error)
153 { // get here, e.g. by NextPingTimer.cancel in stop_pinging
154 if ( error == boost::asio::error::operation_aborted )
155 GlobalLogger.error() << LogPrefix << "Timer for ping was cancelled!"
158 GlobalLogger.error() << LogPrefix << "Received error " << error
159 << " waiting for ping! Stopping";
163 // ping as soon as dns is ready
169 void PingScheduler::ping_when_ready()
173 GlobalLogger.info() << LogPrefix << "waiting for ping request "
174 << "(should take no more than than " << PingIntervalInSec << "s)";
177 else if ( Resolver && Resolver->is_resolving() )
179 GlobalLogger.info() << LogPrefix << "waiting for DNS to finish";
182 else if ( !Resolver )
183 // should not happen, but check anyway
184 GlobalLogger.warning() << LogPrefix << "Have no resolver!";
186 GlobalLogger.info() << LogPrefix << "start ping";
189 // try to get an up-to-date IP (ContinueOnOutdatedIps may only be set
190 // because a CNAME was out of date -- IPs may still be current)
191 HostAddress ip = Resolver->get_next_ip();
193 if ( !ip.is_valid() )
194 { // this can happen in 2 cases: if ContinueOnOutdatedIps==true
195 // or when ip went out of date between resolve and now
196 // --> try to use outdated IP
197 GlobalLogger.info() << LogPrefix << "Checking for outdated IPs";
198 bool check_up_to_date = false;
199 ip = Resolver->get_next_ip(check_up_to_date);
201 if ( !ip.is_valid() )
202 { // still no valid IP --> should not happen
203 GlobalLogger.error() << LogPrefix << "Not even outdated IP to ping "
204 << "-- this should not have happened!! Treat like a failed ping.";
205 if (DnsMaster::get_instance()->get_resolved_ip_ttl_threshold() > 0)
206 GlobalLogger.warning() << LogPrefix << "This probably happened "
207 << "because you specified a TTL threshold > 0 but resolving"
208 << " had no effect on TTLs since external cache is only "
209 << "updated when TTL=0 is reached.";
211 // skip the ping and directly call ping_done_handler
212 ping_done_handler(false);
216 uint32_t ttl = ip.get_ttl().get_updated_value();
219 expiry = "out of date!";
222 boost::posix_time::ptime now =
223 boost::posix_time::second_clock::local_time();
224 expiry = boost::posix_time::to_simple_string(now + seconds(ttl));
227 GlobalLogger.info() << LogPrefix << "pinging IP " << ip.get_ip()
228 << " with TTL " << ttl << "s (" << expiry << ")";
229 Ping->ping( ip.get_ip(),
231 boost::bind(&PingScheduler::ping_done_handler, this, _1) );
236 //------------------------------------------------------------------------------
237 // Post Processing of Ping result
238 //------------------------------------------------------------------------------
241 * @brief called when Ping::ping is done; calls functions to update
242 * statistics, ping interval and elapsed time;
243 * schedules a call to ping, thereby closing the loop
245 void PingScheduler::ping_done_handler( const bool ping_success )
247 GlobalLogger.info() << LogPrefix << "Ping done with success = "
251 // You must call these 3 methods exactly in this order
252 // TODO Fix this method, once it has a semantic dependency with the
253 // update_ping_statistics method, because it depends on the PingAnalyzer
254 // statistics to update the exceeded_ping_failed_limit
255 HostAnalyzer.update_ping_statistics( ping_success );
256 update_ping_interval();
257 update_ping_elapsed_time();
260 { // reset ContinueOnOutdatedIps
261 ContinueOnOutdatedIps = false;
265 // get next protocol, possibly start resolving IPs
266 update_ping_protocol();
268 // schedule next ping
269 (void) NextPingTimer.expires_from_now( seconds( PingIntervalInSec ) );
270 NextPingTimer.async_wait( bind( &PingScheduler::ping, this,
271 boost::asio::placeholders::error ) );
274 void PingScheduler::update_ping_interval()
276 // have to ping more often?
277 if ( HostAnalyzer.exceeded_ping_failed_limit() )
279 PingIntervalInSec.speed_up();
281 GlobalLogger.debug() << LogPrefix << "- Speeding up ping interval to: "
282 << PingIntervalInSec << "s";
286 PingIntervalInSec.back_to_original();
288 GlobalLogger.debug() << LogPrefix << "- Stick to the original ping "
289 << "interval: " << PingIntervalInSec << "s";
293 void PingScheduler::update_ping_elapsed_time()
295 ptime now = microsec_clock::universal_time();
296 time_resolution_traits_adapted64_impl::int_type elapsed_time_in_sec =
297 (now - TimeSentLastPing).total_seconds();
298 GlobalLogger.debug() << LogPrefix << "- Time elapsed since last ping: "
299 << elapsed_time_in_sec << "s";
301 TimeSentLastPing = microsec_clock::universal_time();
305 //------------------------------------------------------------------------------
306 // Ping Protocol Rotation
307 //------------------------------------------------------------------------------
309 void PingScheduler::init_ping_protocol()
311 ProtocolIter = Protocols.end();
312 get_next_ping_protocol();
315 void PingScheduler::update_ping_protocol()
317 if ( can_change_ping_protocol() )
319 get_next_ping_protocol();
323 void PingScheduler::get_next_ping_protocol()
325 GlobalLogger.debug() << LogPrefix
326 << "------------------------------------------------------------------";
328 if (ProtocolIter == Protocols.end())
329 ProtocolIter = Protocols.begin();
330 PingProtocol ping_protocol = *ProtocolIter;
331 // --> ProtocolIter still points to currently used protocol which is
332 // required in dns_resolve_callback
335 Ping->stop_pinging();
337 Ping = PingerFactory::createPinger(ping_protocol, IoService,
338 NetworkInterfaceName, PingReplyTimeout);
340 update_dns_resolver( ping_protocol );
344 bool PingScheduler::can_change_ping_protocol() const
346 // TODO can_change_ping_protocol() and get_next_ping_protocol() may be
347 // implemented in a Algorithm class that can be exchanged in this class to
348 // provide an algorithm neutral class
352 //------------------------------------------------------------------------------
353 // DNS host name resolution
354 //------------------------------------------------------------------------------
356 // show "!" after host name if running on outdated IPs
357 void PingScheduler::update_log_prefix()
359 std::stringstream temp;
360 temp << "Sched(" << DestinationAddress;
361 if (ContinueOnOutdatedIps)
364 LogPrefix = temp.str();
367 void PingScheduler::update_dns_resolver( PingProtocol current_protocol )
369 if (Resolver && Resolver->is_resolving())
370 cancel_resolve(false);
372 if (ContinueOnOutdatedIps)
374 ContinueOnOutdatedIps = false;
378 // DNS master caches created resolvers and resolved IPs, so this will
379 // probably just return an existing resolver with already resolved IPs for
380 // requested protocol ( ICMP/TCP is ignored, only IPv4/v6 is important)
381 Resolver = DnsMaster::get_instance()->get_resolver_for(DestinationAddress,
384 // get number of up-to-date IPs
385 // TODO should check here, if they will be up to date in PingIntervalInSec
386 bool check_up_to_date = true;
387 int ip_count = Resolver->get_resolved_ip_count(check_up_to_date);
390 GlobalLogger.info() << LogPrefix << "Set resolved_ip_count to "
391 << ip_count << " (IPs may be outdated=" << !check_up_to_date << ")";
392 HostAnalyzer.set_resolved_ip_count( ip_count );
394 if (Resolver->is_resolving())
395 GlobalLogger.warning() << LogPrefix << "have up to date IPs but "
396 << "resolver seems to be resolving all the same... "
397 << "Start pinging anyway!";
402 GlobalLogger.info() << LogPrefix
403 << "No up-to-date IPs --> start resolve";
404 start_resolving_ping_address();
405 // set resolved_ip_count will be called in resolve callback
409 void PingScheduler::start_resolving_ping_address()
411 Resolver->async_resolve( boost::bind(&PingScheduler::dns_resolve_callback,
415 void PingScheduler::dns_resolve_callback(const bool was_success,
416 const int recursion_count)
418 GlobalLogger.info() << LogPrefix << "dns resolution finished "
419 << "with success = " << was_success << " "
420 << "after " << recursion_count << " recursions";
424 // trust that a successfull DNS resolve means we have an IP with TTL>0
425 int ip_count = Resolver->get_resolved_ip_count(!ContinueOnOutdatedIps);
427 { // this will create trouble in HostAnalyzer
428 GlobalLogger.warning() << LogPrefix
429 << "Should not have reached this case: resolve was "
430 << "successfull but still have no IPs (up-to-date="
431 << !ContinueOnOutdatedIps << ")!";
432 if (DnsMaster::get_instance()->get_resolved_ip_ttl_threshold() > 0)
433 GlobalLogger.warning() << LogPrefix << "This probably happened "
434 << "because you specified a TTL threshold > 0 but resolving"
435 << " had no effect on TTLs since external cache is only "
436 << "updated when TTL=0 is reached.";
440 GlobalLogger.info() << LogPrefix << "Set resolved_ip_count to "
441 << ip_count << " (IPs may be outdated="
442 << ContinueOnOutdatedIps << ") --> could ping now";
443 HostAnalyzer.set_resolved_ip_count( ip_count );
448 { // host name resolution failed; try again bypassing first outdated CNAME
449 // or using cached IP
450 ContinueOnOutdatedIps = true;
453 std::string skip_host = Resolver->get_skip_cname();
455 if (skip_host.empty())
456 { // continue with IP
457 GlobalLogger.notice() << LogPrefix << "DNS failed, "
458 << "try anyway with cached data";
460 int ip_count = Resolver->get_resolved_ip_count(false);
461 GlobalLogger.info() << LogPrefix << "Set resolved_ip_count to "
462 << ip_count << " (IPs may be outdated=" << true << ")";
463 HostAnalyzer.set_resolved_ip_count( ip_count );
468 { // have CNAME to continue
469 GlobalLogger.notice() << LogPrefix << "DNS failed, "
470 << "try again skipping a CNAME and resolving "
471 << skip_host << " directly";
473 cancel_resolve(false);
475 // now create new resolver
476 Resolver = DnsMaster::get_instance()
477 ->get_resolver_for(skip_host, *ProtocolIter);
478 start_resolving_ping_address();
484 * cancel resolver if force_cancel or if it is not resolving DestinationAddress
486 * Resolvers have a life on their own: they are cached by DnsMaster so never go
487 * out of scope and even after calling callbacks, there might still be a
488 * longterm timer active to re-try resolving.
489 * We want to cancel that long-term timer only if the Resolver is not for our
490 * real, original DestinationAddress but a CNAME, which can happen when trying
491 * to skip cnames and working on out-dated IPs
493 void PingScheduler::cancel_resolve(const bool force_cancel)
497 GlobalLogger.info() << "Cancelling resolver (forced)";
498 Resolver->cancel_resolve();
500 else if ( Resolver->get_hostname() == DestinationAddress )
501 GlobalLogger.info() << LogPrefix
502 << "Leave original resolver active in background";
505 GlobalLogger.info() << LogPrefix << "Cancel resolver for "
506 << Resolver->get_hostname() << " since is not the original "
507 << DestinationAddress;
508 Resolver->cancel_resolve();