--- summary: Federation doesn't play nice with IPv6 --- created: 2015-02-01 12:26:18.0 creator: matthew description: "Servers with v6 resolvers seem to have problems federating - see synacktik from #matrix:matrix.org:\n\nFeb 1 12:31\n http://pastebin.com/giEhadsG\n\n\ni have ipv6 running on this server, yeah\t\nFeb 1 12:55\n dual stack\t\nFeb 1 12:59\n well thats interesting\t\nFeb 1 13:00\n removed my v6 resolvers" id: '10990' key: SYN-254 number: '254' priority: '2' project: '10000' reporter: matthew status: '1' type: '1' updated: 2016-11-07 18:27:41.0 votes: '0' watches: '4' workflowId: '11090' --- actions: - author: matthew body: |- The problem seems to be that twisted's http agent is hardcoded to ipv4: http://twistedmatrix.com/pipermail/twisted-python/2012-August/026012.html created: 2015-03-14 00:33:33.0 id: '11392' issue: '10990' type: comment updateauthor: matthew updated: 2015-03-14 00:33:33.0 - author: matthew body: |- ...and our federation endpoint is hardcoded to ipv4 too: {code} if ssl_context_factory is None: transport_endpoint = TCP4ClientEndpoint default_port = 8008 else: transport_endpoint = SSL4ClientEndpoint endpoint_kw_args.update(sslContextFactory=ssl_context_factory) default_port = 8448 {code} created: 2015-03-14 00:53:43.0 id: '11393' issue: '10990' type: comment updateauthor: matthew updated: 2015-03-14 00:53:59.0 - author: sanderr body: |- Twisted uses its own resolver lib, which plays nice with IPv4 addresses, but not with IPv6. Related to [twisted ticket #4362|https://twistedmatrix.com/trac/ticket/4362]. {code:python} python -m twisted.conch.stdio >>> from twisted.names import client >>> resolver = client.createResolver(servers=[('2001:4860:4860::8888', 53)]) >>> resolver.getHostByName('google.com') >> >>> resolver = client.createResolver(servers=[('8.8.8.8', 53)]) >>> resolver.getHostByName('google.com') >>> {code} created: 2015-08-19 13:22:40.0 id: '12066' issue: '10990' type: comment updateauthor: sanderr updated: 2015-08-19 13:24:56.0 - author: richvdh body: 'Migrated to github: https://github.com/matrix-org/synapse/issues/1279' created: 2016-11-07 18:27:41.0 id: '13598' issue: '10990' type: comment updateauthor: richvdh updated: 2016-11-07 18:27:41.0