<div class="__aliyun_email_body_block"><div  style="clear:both;"><span  style="font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;">Hi, Chriztoffer. Thanks for your reply.</span></div><div  style="clear:both;"><br ></div><div  style="clear:both;">I noticed Cisco router has to specify anycast command when config an anycast address as follows(https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipv6_basic/configuration/xe-3se/5700/ip6-anycast-add-xe.html):</div><div  style="clear:both;"><span  class="synph" style="margin:.0px;padding:.0px;border:.0px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-weight:400;font-stretch:inherit;font-size:14.0px;line-height:inherit;font-family:CiscoSans,Arial,sans-serif;vertical-align:baseline;overflow:visible;color:#58585b;text-align:start;text-indent:.0px;text-transform:none;widows:2;background-color:#ffffff;text-decoration-thickness:initial;text-decoration-style:initial;text-decoration-color:initial;"><span  class="kwd" style="margin:.0px;padding:.0px;border:.0px;font-style:inherit;font-variant:inherit;font-weight:bold;font-stretch:inherit;font-size:14.0px;line-height:inherit;font-family:CiscoSans,Arial,sans-serif;vertical-align:baseline;overflow:visible;">ipv6</span> <span  class="kwd" style="margin:.0px;padding:.0px;border:.0px;font-style:inherit;font-variant:inherit;font-weight:bold;font-stretch:inherit;font-size:14.0px;line-height:inherit;font-family:CiscoSans,Arial,sans-serif;vertical-align:baseline;overflow:visible;">address</span> </span><span  class="synph" style="margin:.0px;padding:.0px;border:.0px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-weight:400;font-stretch:inherit;font-size:14.0px;line-height:inherit;font-family:CiscoSans,Arial,sans-serif;vertical-align:baseline;overflow:visible;color:#58585b;text-align:start;text-indent:.0px;text-transform:none;widows:2;background-color:#ffffff;text-decoration-thickness:initial;text-decoration-style:initial;text-decoration-color:initial;"><span  class="var" style="margin:.0px;padding:.0px;border:.0px;font-style:italic;font-variant:inherit;font-weight:inherit;font-stretch:inherit;font-size:14.0px;line-height:inherit;font-family:CiscoSans,Arial,sans-serif;vertical-align:baseline;overflow:visible;">ipv6-prefix/prefix-length</span> </span><span  class="synph" style="margin:.0px;padding:.0px;border:.0px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-variant-numeric:inherit;font-variant-east-asian:inherit;font-weight:400;font-stretch:inherit;font-size:14.0px;line-height:inherit;font-family:CiscoSans,Arial,sans-serif;vertical-align:baseline;overflow:visible;color:#58585b;text-align:start;text-indent:.0px;text-transform:none;widows:2;background-color:#ffffff;text-decoration-thickness:initial;text-decoration-style:initial;text-decoration-color:initial;"><span  class="kwd" style="margin:.0px;padding:.0px;border:.0px;font-style:inherit;font-variant:inherit;font-weight:bold;font-stretch:inherit;font-size:14.0px;line-height:inherit;font-family:CiscoSans,Arial,sans-serif;vertical-align:baseline;overflow:visible;">anycast</span></span></div><div  style="clear:both;">So when I using FRR routing suite, should I specify the address is an anycast address with some specific command or just specify two same address on two different interfaces?</div><div  style="clear:both;"><br ></div><div  style="clear:both;">Actually I have tested the ipv6 anycast using a commercial H3C router (whose anycast address configuration command is similar to Cisco). I used 3 routers to form a triangular topology with R1 on the top and R2 on the bottom-left and R3 on the bottom-right. R1/2/3 connects to PC1/2/3, respectively. I config R2 and R2 with unicast address 4001::1 (with command: ipv6 address 4001::1/64 anycast). Then I ping 4001::1 from PC1 with just PC2 connected and PC3 unconnected as well as with just PC3 connnected and PC2 unconnected. In both scenario, the ping can get reply.</div><div  style="clear:both;"><br ></div><div  style="clear:both;">After that, my plan is to replace R2 and R3 with an open source router running such as FRR. However, I cannot find the corresponding config command similar to what I used on the commercial router (which is <span  style="color:#000000;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;text-align:start;text-indent:.0px;text-transform:none;widows:2;background-color:#ffffff;text-decoration-thickness:initial;text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline;">ipv6 address 4001::1/64 anycast</span>). That's what confused me.</div><div  style="clear:both;"><br ></div><div  style="clear:both;"><span  style="color:#000000;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;text-align:start;text-indent:.0px;text-transform:none;widows:2;background-color:#ffffff;text-decoration-thickness:initial;text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline;">So back to the question at the start of this email: when I using FRR routing suite, should I specify the address is an anycast address with some specific command or just specify two same address on two different interfaces?</span></div><div  style="clear:both;"><span  style="font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;"><br ></span></div><div  style="clear:both;"><span  style="font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;">York</span></div><div  style="clear:both;"><span  style="font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;"><br ></span></div><blockquote  style="margin-right:.0px;margin-top:.0px;margin-bottom:.0px;"><div  style="clear:both;"><span  style="font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;">------------------------------------------------------------------</span></div><div  style="clear:both;"><span  style="font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;">发件人：Chriztoffer Hansen <ch@ntrv.dk></span></div><div  style="clear:both;"><span  style="font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;">发送时间：2021年2月27日(星期六) 11:13</span></div><div  style="clear:both;"><span  style="font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;">收件人：yanhc519 <yanhc519@aliyun.com></span></div><div  style="clear:both;"><span  style="font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;">抄　送：frog@lists.frrouting.org <frog@lists.frrouting.org></span></div><div  style="clear:both;"><span  style="font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;">主　题：Re: [FROG] How to test ipv6 anycast address with frr routing?</span></div><div  style="clear:both;"><span  style="font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;"><br ></span></div>On Sat, 27 Feb 2021 at 01:09, yan via frog <frog@lists.frrouting.org> wrote:<br >> does frr routing support ipv6 anycast address configuration?<br ><br >Anycast routing in the essence of things is "just" announcing the same<br >prefix from multiple locations.<br ><br >> How could I test ipv6 anycast address with frr routing?<br ><br >In the simplest of set-ups, configure multiple hosts to originate the<br >same prefix (e.g. /32, /128) That would be anycast at the most basic<br >level.<br ><br >(What services you will want to host from the anycast IP(s) is at your<br >own descretion.)<br ><br >> Is there a tutorial about this?<br ><br >The official docs https://docs.frrouting.org does not contain such a<br >tutorial. Thou I suspect more than one blogpost, conference talk has<br >been given on the topic over the years (not being FRRouting specific).<br >But most always this will be a generalized one. Skipping any in-depth<br >(SW specific) tutorial content. And "just" explaining the concept.<br ><br >-- <br >Chriztoffer</blockquote><div ><br ></div></div>