Hello, I tried even a specific OID.
I am using snmpwalk on localhost with .1.3.6. I hope this should generate some requests that could be passed to the handler function. On the agent side I am getting Connection from UDP: [127.0.0.1]:-32767 On the snmpwalk side I am getting request timeout. M. On Thu, August 9, 2007 5:42 pm, Graeme Wilson wrote: > Hi, > > > Hmm, ok. > All I can really suggest is that you try doing some debug - maybe > instead of registering a generic OID, try registering a specific OID for a > test and then try doing a get on that. How are you running the agent and > how are you performing the get? > > Maybe some others on here could help you turning the Debug on for more > trace messages. I'll keep thinking and get back to you with any other > suggestions. > > Cheers > G > > > > > >> -----Original Message----- >> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] >> Sent: 09 August 2007 16:09 >> To: Graeme Wilson >> Cc: net-snmp-users@lists.sourceforge.net >> Subject: RE: Newbie question: writing a simple agent >> >> >> Hello Graeme, >> >> >> thanks for your prompt reply. >> >> netsnmp_register_handler( reg ) is "hidden" in >> >> printf("returned=%d\n", netsnmp_register_handler(reg)); >> >> I tried it before without printf and it was doing the same thing. >> >> >> I have no other handlers and no other agents started. >> >> >> I considered switching snmp logging with LOG_DEBUG >> level/priority but I did not find any function how to set the level. >> >> Is there anything else I could try? >> >> >> Thanks. >> >> >> Milan >> >> >> On Thu, August 9, 2007 4:53 pm, Graeme Wilson wrote: >> >>> Hi Milan, >>> >>> >>> >>> From a quick look at your code it looks like you've missed >>> >> a crucial >>> line to register the handler: >>> >>> netsnmp_register_handler( reg ); >>> >>> Which you need to do after your line: >>> reg = netsnmp_handler_registration_create(...) >>> >>> Also, one important point (I forgot to mention previously), >>> >> if there >>> are any other handlers which register for specific OIDs (e.g. >>> .1.3.6.1.2.1.1.4.0) - these will be called instead of your generic >>> handler. >>> >>> Hope that helps. >>> Graeme >>> >>> >>> >>> >>> >>> >>> >>>> -----Original Message----- >>>> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] >>>> Sent: 09 August 2007 15:43 >>>> To: Graeme Wilson >>>> Cc: net-snmp-users@lists.sourceforge.net >>>> Subject: RE: Newbie question: writing a simple agent >>>> >>>> >>>> >>>> Hello Graeme, >>>> >>>> >>>> >>>> sorry for bothering you again. >>>> >>>> I have tried to merge your code with MFD code. I am >>>> >> obviously doing >>>> something wrong. When I run snmpwalk on the agent I can see that >>>> agent_check_and_process(1) in the main loop finishes but >> the handler >>>> does not get called. >>>> >>>> I get error message from the agent: >>>> >>>> >>>> >>>> Connection from UDP: [127.0.0.1]:-32767 >>>> >>>> >>>> >>>> I assume this means this request was not handled by the agent. >>>> >>>> >>>> >>>> I do not know if netsnmp_register_handler(reg) is successful, it >>>> returns 0. I was googling but I did not find meaning of this value. >>>> >>>> Did I miss something in my main()? I am attaching short code. >>>> >>>> >>>> >>>> Thank you and please do net get angry with me for so many mails. >>>> >>>> >>>> >>>> Milan >>>> >>>> >>>> >>>> ---- >>>> >>>> >>>> >>>> >>>> #include "agent.h" >>>> #include "agent_error.h" >>>> >>>> >>>> >>>> static int keep_running; >>>> >>>> void stop_server(UNUSED int a) { keep_running = 0; } >>>> >>>> >>>> /* Ippc function which will be called for all OIDs below >>>> >> the root one >>>> registered above */ int IppcOidHandler(UNUSED netsnmp_mib_handler >>>> *handler, UNUSED netsnmp_handler_registration *reginfo, UNUSED >>>> netsnmp_agent_request_info *reqinfo, netsnmp_request_info >> *requests) >> >>>> { int ret = SNMP_ERR_NOERROR; >>>> >>>> >>>> printf("Received SNMP request"); for (unsigned i = 0; i < >>>> requests->range_end_len; i++) { printf("%d.", >>>> (int)requests->range_end[i]); >>>> } >>>> printf("\n"); >>>> >>>> switch(reqinfo->mode) { case MODE_GET: /* Call some other code to >>>> process the 'requests' argument */ //ret = myData->getData( requests >>>> ); break; case >>>> MODE_GETNEXT: /* Call some other code to process the 'requests' >>>> argument */ //ret = myData->getNextData( requests ); >> break; default: >>>> /* we should never get here in my code */ //iRet = >>>> >> SNMP_ERR_GENERR; >> >>>> break; } return 1; //ret; } >>>> >>>> >>>> int main (UNUSED int argc, UNUSED char **argv) { >> netsnmp_mib_handler >>>> *handler; netsnmp_handler_registration *reg; >>>> >>>> >>>> static oid root_oid[] = { 1, 3, 6 }; >>>> >>>> snmp_enable_stderrlog(); >>>> >>>> SOCK_STARTUP; >>>> >>>> >>>> >>>> init_agent("ippc agent"); >>>> >>>> init_snmp("ippc agent"); >>>> >>>> init_master_agent(); /* open the port to listen on (defaults to >>>> udp:161) */ >>>> >>>> >>>> >>>> keep_running = 1; signal(SIGTERM, stop_server); signal(SIGINT, >>>> stop_server); >>>> >>>> handler = netsnmp_create_handler("IppcOIDHandler", >> &IppcOidHandler ); >> >>>> >>>> >>>> if (handler) { reg = netsnmp_handler_registration_create( >>>> "IppcHandler", handler, root_oid, OID_LENGTH(root_oid), 0); >>>> >>>> >>>> >>>> printf("returned=%d\n", netsnmp_register_handler(reg)); } else { >>>> exit(1); } >>>> >>>> >>>> >>>> while(keep_running) { agent_check_and_process(1); /* 0 == >> don't block >>>> */ printf("mainloop\n"); } >>>> >>>> >>>> >>>> /* at shutdown time */ >>>> netsnmp_unregister_handler(reg); snmp_shutdown("ippc agent"); >>>> SOCK_CLEANUP; >>>> >>>> >>>> >>>> return 0; } >>>> >>>> >>>> >>>> >>>> >>>> ---- >>>> >>>> >>>> >>>> >>>> On Wed, August 8, 2007 4:10 pm, Graeme Wilson wrote: >>>> >>>> >>>>> Hi Milan, >>>>> >>>>> >>>>> >>>>> >>>>> No worries about the questions. >>>>> >>>>> >>>>> >>>>> >>>>> For my subagent (binary/executable) I doctored an existing >>>>> >>>>> >>>> 'main' that >>>> >>>> >>>>> I had from when I'd created a subagent with mib2c - its >>>>> >>>>> >>>> just like your >>>>> example below: - init_agent - etc etc - register your handler here >>>>> - loop (agent_check_and_process) >>>>> - etc etc >>>>> >>>>> >>>>> >>>>> >>>>> Cheers >>>>> Graeme >>>>> >>>>> >>>>> >>>>> >>>>> >>>>>> -----Original Message----- >>>>>> From: [EMAIL PROTECTED] >>>>>> >> [mailto:[EMAIL PROTECTED] >> >>>>>> Sent: 08 August 2007 14:47 >>>>>> To: Graeme Wilson >>>>>> Cc: net-snmp-users@lists.sourceforge.net >>>>>> Subject: RE: Newbie question: writing a simple agent >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> Hello Graeme, >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> I went through your code and it seems it is exactly what I >>>>>> need. >>>>>> >>>>>> >>>>>> >>>>>> I am just confused about one thing: how does it plug into >>>>>> snmpd? >>>>>> >>>>>> >>>>>> >>>>>> I understand that I need to do in agent main() registration >>>>>> (and >>>>>> un-registration at agent finish) but what do I actually >> generate? >>>>>> >>>>>> Should I create a binary like in MFD example and loop using >>>>>> agent_check_and_process() or snmp_select_info() or >> should I create >>>>>> some kind of .so that does mere regsitration and finishes? >>>>>> >>>>>> In the former case the scenario is >>>>>> - init_agent >>>>>> - init_snmp >>>>>> - init_master_agent(); >>>>>> - register handler >>>>>> - loop >>>>>> - un-register handler >>>>>> - snmp_shutdown >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> or am I missing something? >>>>>> >>>>>> Sorry for asking you newbie trivial questions :-) >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> Thanks. >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> Milan >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> On Wed, August 8, 2007 11:11 am, Graeme Wilson wrote: >>>>>> >>>>>> >>>>>> >>>>>>> >>>>>> >>>>>>> Hi, >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> I have done something similar recently (I provide some >>>>>>> >>>>>>> >>>> sample code >>>>>>> below - but note that ultimately everything is still done >>>>>>> within >>>>>>> >>>>>> the agent). >>>>>>> My Agent simply registers the root OID of the MIB it will >>>>>>> >>>>>>> >>>>>>> >>>>>> handle and >>>>>>> some other function knows all about the data and the >>>> specific OIDs >>>>>>> that the Agent handles. I just registered a generic >>>> handler for the >>>>>>> root oid and >>>>>> then when it >>>>>>> is called, the handler make appropriate calls to handle the >>>>>> request. >>>>>>> I guess in your case you could then request the data (if >>>>>>> >>>>>>> >>>>>>> >>>>>> any) from the >>>>>>> process/thread that holds the Data and OIDS. >>>>>>> >>>>>>> Hope that helps. >>>>>>> Graeme >>>>>>> ------------- >>>>>>> /* In your main/initialise function */ >>>>>>> netsnmp_mib_handler* handler = netsnmp_create_handler( >>>>>>> "GenericOIDHandler", &genericOidHandler ); >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> netsnmp_handler_registration* reg = >>>>>>> netsnmp_handler_registration_create( "GenericHandler", >>>>>>> handler, root_oid, OID_LENGTH(root_oid), 0 ); >>>>>>> >>>>>>> netsnmp_register_handler( reg ); >>>>>>> >>>>>>> >>>>>>> >>>>>>> /* Generic function which will be called for all OIDs below >>>>>>> >>>>>>> >>>>>>> >>>>>> the root >>>>>>> one registered above */ int genericOidHandler( >>>> netsnmp_mib_handler >>>>>>> *handler, netsnmp_handler_registration *reginfo, >>>>>>> netsnmp_agent_request_info *reqinfo, netsnmp_request_info >>>>>> *requests ) >>>>>> >>>>>> >>>>>> >>>>>>> { int ret = SNMP_ERR_NOERROR; >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> switch(reqinfo->mode) { case MODE_GET: /* Call some >> other code to >>>>>>> process the 'requests' argument */ ret = myData->getData( >>>> requests >>>>>>> ); break; case MODE_GETNEXT: /* Call some other code to >>>>>>> >>>>>>> >>>> process the >>>>>>> 'requests' >>>>>>> argument */ ret = myData->getNextData( requests ); break; >>>> default: >>>> >>>> >>>>>>> /* we should never get here in my code */ iRet = >>>>>>> >> SNMP_ERR_GENERR; >> >>>>>>> break; } return ret; } >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>>> -----Original Message----- >>>>>>>> From: [EMAIL PROTECTED] >>>>>>>> [mailto:[EMAIL PROTECTED] On >>>>>>>> >>>>>>>> >>>> Behalf Of >>>> >>>> >>>>>>>> [EMAIL PROTECTED] >>>>>>>> Sent: 08 August 2007 06:51 >>>>>>>> To: Mike Ayers >>>>>>>> Cc: net-snmp-users@lists.sourceforge.net >>>>>>>> Subject: RE: Newbie question: writing a simple agent >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> Hello Mike, >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> thanks for replying to my question. >>>>>>>> >>>>>>>> I understand that a standard approach is to register the >>>>>>>> >>>>>>>> >>>>>>>> >>>>>> agent for a >>>>>>>> range of OISs and to let the agent to be OID aware while >>>> the other >>>>>>>> process should take care of the underlaying data. >>>>>>>> >>>>>>>> However, I was asked to write an agent that would NOT be >>>>>>>> >>>>>>>> >>>>>>>> >>>>>> OID-aware. >>>>>> >>>>>> >>>>>> >>>>>>>> All it would know it is responsible for a range of >>>>>>>> >> OIDs without >> >>>>>>>> knowing any details. It would forward complete OIDs to >> the other >>>>>>>> process that would take care about OID >>>>>> disassembly/translation, data >>>>>>>> manipulation etc. >>>>>>>> >>>>>>>> I am wondering if this is possible within the Net SNMP >>>>>>>> >>>>>>>> >>>> API, at all. >>>> >>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> If so, where should I start? >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> Thanks. >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> Milan >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On Tue, August 7, 2007 11:44 pm, Mike Ayers wrote: >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>>>>> From: [EMAIL PROTECTED] >>>>>>>>>> [mailto:[EMAIL PROTECTED] On >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>> Behalf Of >>>>>> >>>>>> >>>>>> >>>>>>>>>> [EMAIL PROTECTED] >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>>> The agent itself will not be aware of individual OIDs >>>>>>>>>> >>>>>>>>>> >>>> and their >>>>>>>>>> meaning. This will be done by the other process that >>>>>>>>>> also >>>>>>>> holds the >>>>>>>>>> actual data. >>>>>>>>> >>>>>>>>> This is a bit of a design problem as stated. The >>>>>>>>> >> (sub)agent is >> >>>>>>>>> responsible for managing its OID range, and therefore >> it is not >>>>>>>>> possible to have a subagent completely unaware of the >>>>>>>>> OIDs. >>>>>>>>> >>>>>>>>> >>>>>>>> This does >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>>> not, however, mean that the subagent needs to be aware of >>>>>>>>> >>>>>> the data >>>>>>>>> underlying the MIB. >>>>>>>>> >>>>>>>>> A common paradigm is to have the subagent register for >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>> the range of >>>>>>>>> values (table, MIB, whatever) that it will manage, and >>>>>> have the OP >>>>>>>>> (other >>>>>>>>> process) manage the data within the range. The agent >> does OID >>>>>>>>> assembly/disassembly (i.e. breaking OIDs into range part >>>>>>>> and specific >>>>>>>>> part), possibly reformat the specific part to make it >>>>>>>>> more understandable to the OP (thus only the subagent need >>>>>>>>> be >>>>>>>> MIB aware). >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>>> The OP returns the values for the requested data, then >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>> the subagent >>>>>>>>> formats and assembles the response. >>>>>>>>> >>>>>>>>> >>>>>>>>> HTH, >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> Mike >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>> >>>> >> --------------------------------------------------------------------- >> >>>> >>>>>> >>>>>>>> - >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>>> --- This SF.net email is sponsored by: Splunk Inc. >>>>>>>>> Still grepping through log files to find problems? Stop. >>>>>>>>> Now Search log events and configuration files using AJAX >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> and a browser. >>>>>>>>> Download your FREE copy of Splunk now >> >>>>>>>>> >>>>>>>>> >>>> http://get.splunk.com/ >>>> >>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Net-snmp-users mailing list >>>>>>>>> Net-snmp-users@lists.sourceforge.net >>>>>>>>> Please see the following page to unsubscribe or change >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> other options: >>>>>>>>> https://lists.sourceforge.net/lists/listinfo/net-snmp-use >>>>>>>>> rs >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> ----------------------------------------------------------- >>>>>>>> --- >>>>>>>> ----------- >>>>>>>> This SF.net email is sponsored by: Splunk Inc. >>>>>>>> Still grepping through log files to find problems? Stop. >>>>>>>> Now Search log events and configuration files using AJAX and >>>>>>>> a browser. Download your FREE copy of Splunk now >> >>>>>>>> http://get.splunk.com/ >>>>>>>> _______________________________________________ >>>>>>>> Net-snmp-users mailing list >>>>>>>> Net-snmp-users@lists.sourceforge.net >>>>>>>> Please see the following page to unsubscribe or change >>>>>>>> >>>>>>>> >>>>>>>> >>>>>> other options: >>>>>>>> https://lists.sourceforge.net/lists/listinfo/net-snmp-users >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>> >>>> >> --------------------------------------------------------------------- >> >>>> >>>>>> - >>>>>> >>>>>> >>>>>> >>>>>>> --- This SF.net email is sponsored by: Splunk Inc. >>>>>>> Still grepping through log files to find problems? Stop. >>>>>>> Now Search log events and configuration files using AJAX >>>>>>> >>>>>>> >>>>>>> >>>>>> and a browser. >>>>>>> Download your FREE copy of Splunk now >> >>>>>>> >> http://get.splunk.com/ >> >>>>>>> _______________________________________________ >>>>>>> Net-snmp-users mailing list >>>>>>> Net-snmp-users@lists.sourceforge.net >>>>>>> Please see the following page to unsubscribe or change >>>>>>> >>>>>>> >>>>>>> >>>>>> other options: >>>>>>> https://lists.sourceforge.net/lists/listinfo/net-snmp-users >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>> >>>> >>>> >>>> >>> >>> >> >> >> >> > > ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Net-snmp-users mailing list Net-snmp-users@lists.sourceforge.net Please see the following page to unsubscribe or change other options: https://lists.sourceforge.net/lists/listinfo/net-snmp-users
