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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='mso-fareast-language:EN-US'>In order to use YANG you need a device that can speak NETCONF/RESTCONF and understands YANG.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>There’s no such thing as “The YANG ACL” -there’s IETF YANG model for ACLs, there’s OpenConfig one, and your switch vendor might have another YANG model for representing ACLs. <o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Whichever model provides sufficient coverage for your use case (i.e. can use the model to specify SRC/DST/MASK/DENY/ACCEPT) and is supported natively by your device (can send the ACL config in this format to the device at it knows what to do) is the right for you. <o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>If your devices do not support NETCONF/RESTCONF nor understand YANG you can still push the ACL changes via CLI scraping (Ansible)<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Now in either case (netconf-yang/ansible), what you’re better off with is a tool that allows operator to enter the details of the ACL line to be added (details of the flow) and just take that input and insert it into the pre-defined/prepared template (yang/ansible template), then the script just prompts the resulting config to be pushed onto the device (devices).<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'> <o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>adam<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span lang=EN-US>From:</span></b><span lang=EN-US> NANOG <nanog-bounces@nanog.org> <b>On Behalf Of </b>Douglas Fischer<br><b>Sent:</b> Tuesday, June 16, 2020 7:40 PM<br><b>To:</b> nanog@nanog.org<br><b>Subject:</b> BGP FLowspec to Yang/Yaml ACL<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>We were looking for some way to implement BGP Flowspec Filtering(just the permit/deny basic) using L3 switches in an automated way.<br><br>Searching a bit we found <a href="https://github.com/ios-xr/bgpfs2acl"><span style='font-family:"Arial",sans-serif'>https://github.com/ios-xr/bgpfs2acl</span></a><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-size:12.0pt;font-family:"Courier New"'>Is almost what we are looking for!<br>But is focused on Cisco devices.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>We even considered fork it to our specific vendor.<br>But before reinventing the wheel, I decide to ask to colleagues if anybody knows some tool that converts BGP Flowspec ACLs into YAML or even to YANG.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>If that exists, with Ansible/Netconf/RestConf(or some similar tool), it would be easy to delegate to Switchs doing the basic filtering that only More expensive Routers can do by now.<br><br><br>P.S.: This Idea does not include(on the first moment) more complex features of Flowspec like Redirect ou Rate-Limt.<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>Any suggestions or ideas? <o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>-- <o:p></o:p></p><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Douglas Fernando Fischer<br>Engº de Controle e Automação</span><o:p></o:p></p></div></div></div></div></body></html>