1 PerfSONAR implementation using Netconf Network Monitoring Workshop October 21, 2009 Arne Øslebø

2 perfSONAR overview ● infrastructure for network performance monitoring across multiple administrative domains ● Defines several services – Measurement Point – Measurement Archive – Lookup Service – Authentication Service – Transformation Service – Topology Service ● Based on XML protocol NMWG

3 How can intelligent traceroute be improved? ● Answer: improve perfSONAR ● Several limitations with todays perfSONAR – Only supports SNMP MP – Limited to a fixed set of metrics ● What about passive monitoring probes with more detailed metrics? – Code change needed ● Should be possible to display all available metrics for a link regardless of source – Predefined default set of metrics – Extended metrics on request

4 Generic Information Model ● Current perfSONAR lacks generic information model for MA and MP ● Today there are many implementations – RRD-MA, SQL-MA, Hades-MA – Ping-MP, SSH-MP, SNMP-MP ● Clients need special code for each implementation ● Should be possible to have generic user interfaces that supports all MP and MA – New metrics added without any changes to code base ● Need a template system for describing data contained in MP and MA

5 Problems with perfSONAR protocol (NMWG) ● Does not follow well established practice of separating information model from transport protocol. ● Message inconsistency – Very little message validation ● RelaxNG alone is not enough to formally define a proper information model – Example: YANG in Netconf uses Relax NG, Schematron and DSRL. ● MA and MP too hardcoded (no generic querying) – LS uses XQuery. Better, but should be integrated feature of the base protocol. Still no validation of messages.

6 NMWG query – self test

7 NMWG response – self test GEANT2/random-fetch-test/success/

8 Our solution ● perfSONAR is an implementation of distributed management ● Researchers and standardization bodies have worked on this for years – WSDM (OASIS), WS-management (DTMF) and to some extent Netconf (IETF). ● Do we really need NMWG? – No. Existing protocols can do the job. ● WSDM and WS-management more mature ● We selected Netconf as it is an IETF standard and we are familiar with it. – Goal: use off the shelf Netconf tools to query perfSONAR infrastructure

9 MA information model in YANG measurementArchive |-sysinfo |-datasources |-source |-name |-type |-selftest |-obspoints |-groups |-template |-timeperiods |-timeperiod |-id |-starttime |-duration |-reports container selftests { list test { key "name"; leaf name { mandatory "true"; type string; description "Name of test"; } leaf description { mandatory "true"; type string; description "Description of test"; } leaf status { mandatory "true"; type enumeration { enum "passed"; enum "failed"; } description "Status of test"; }

10 Querying the MA $msg=array("message-id"=>1, "getconfig"=>array('source'=>array('running',""), 'filter'=>array('type'=>'xpath', 'select'=>"/measurementArchive/datasources/source[name='ssmping']/selftests/test"))); $return = (array)$client->rpc($msg); PHP code: XML message:

11 Response dbConnect Test database connection passed timeperiod Test to see if any time periods exists in the database failed /measurementArchive/datasources/source[name='ssmping']/ selftests/test[status='failed'] Validated

12 Implementation ● Based on Stager – MA and user interface for MA ● MA information model created for easy implementation – Good starting point, but needs more work for proper implementation ● Low code base for Stager implementation – < 900 lines of code ● No plotting, no proper Xpath support ● Simple RRD MA – < 400 lines of code, works with Stager front end

13 Summary and recommendations ● Our prototypes show that: – Netconf and Yang are well suited for perfSONAR – Possible to create self documenting template system for MA – Flexible querying – Proper validation of messages – Easy to implement ● Our (radical?) suggestions: – Drop NMWG – why compete against already standardized protocols? – Use experience from NMWG to create formal YANG models – Help IETF to standardize any missing features in Netconf and Yang ●