Ipv6
除非指定 +trace,否則 ipv6 反向 dns 不起作用
我正在嘗試在我的區域網路中為 ipv6 設置反向 dns。應委派的 dns 伺服器位於 2001:5c0:1400:b::9,RDNS 應為其工作的主機位於 2001:5c0:1500:300::1。問題是,除非指定 +trace,否則 dig -x 似乎不起作用:
$ dig -x 2001:5c0:1500:300::1 ; <<>> DiG 9.9.5-3-Ubuntu <<>> -x 2001:5c0:1500:300::1 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 24545 ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4096 ;; QUESTION SECTION: ;1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.3.0.0.0.5.1.0.c.5.0.1.0.0.2.ip6.arpa. IN PTR ;; Query time: 714 msec ;; SERVER: 192.168.0.1#53(192.168.0.1) ;; WHEN: Sun Oct 19 23:31:58 CEST 2014 ;; MSG SIZE rcvd: 101 $ dig -x 2001:5c0:1500:300::1 +trace ; <<>> DiG 9.9.5-3-Ubuntu <<>> -x 2001:5c0:1500:300::1 +trace ;; global options: +cmd . 433182 IN NS l.root-servers.net. . 433182 IN NS a.root-servers.net. . 433182 IN NS f.root-servers.net. . 433182 IN NS c.root-servers.net. . 433182 IN NS h.root-servers.net. . 433182 IN NS i.root-servers.net. . 433182 IN NS g.root-servers.net. . 433182 IN NS e.root-servers.net. . 433182 IN NS b.root-servers.net. . 433182 IN NS j.root-servers.net. . 433182 IN NS k.root-servers.net. . 433182 IN NS d.root-servers.net. . 433182 IN NS m.root-servers.net. . 435889 IN RRSIG NS 8 0 518400 20141025170000 20141018160000 22603 . kvgfN/rC3esMrbGF3KZFrwogm1EKA+nwZrFMXHf3a9sJsDZdpe4iDrOB 0xKyu9dvcsdfLcVLDMHGojlQqUAOda9KIcOGIdeFXl3IOKAk91XvQfrq mLOz02vrBog6gfFnzA34lGkLan1BtRFqKkjxvIHUyIcxstZkak44p/2/ t1w= ;; Received 913 bytes from 192.168.0.1#53(192.168.0.1) in 369 ms ip6.arpa. 172800 IN NS d.ip6-servers.arpa. ip6.arpa. 172800 IN NS b.ip6-servers.arpa. ip6.arpa. 172800 IN NS c.ip6-servers.arpa. ip6.arpa. 172800 IN NS e.ip6-servers.arpa. ip6.arpa. 172800 IN NS f.ip6-servers.arpa. ip6.arpa. 172800 IN NS a.ip6-servers.arpa. ip6.arpa. 86400 IN DS 13880 8 2 068554EFCB5861F42AF93EF8E79C442A86C16FC5652E6B6D2419ED52 7F344D17 ip6.arpa. 86400 IN RRSIG DS 8 2 86400 20141026190000 20141019180000 10069 arpa. oRqujHjYlEPu3LNM61WtGMXvMyXYYxvBnTPxYLhZxs3rZxqLNaqmzMQr 5cGjUBoEPbAQSsSvpXBX/VHKRf0FjcpL1kXt6YcmzwMyMKdlQrC9Rrxz AQd1csbsfpJP6E6AwWz3Vbd/AnsghIk+BRKerC2+DxjCxU8UpV9ae/3v R0o= ;; Received 685 bytes from 192.33.4.12#53(c.root-servers.net) in 77 ms 1.0.c.5.0.1.0.0.2.ip6.arpa. 86400 IN NS ns2.gogo6.com. 1.0.c.5.0.1.0.0.2.ip6.arpa. 86400 IN NS ns1.gogo6.com. 1.0.c.5.0.1.0.0.2.ip6.arpa. 10800 IN NSEC 8.c.5.0.1.0.0.2.ip6.arpa. NS RRSIG NSEC 1.0.c.5.0.1.0.0.2.ip6.arpa. 10800 IN RRSIG NSEC 5 11 10800 20141102202721 20141019192721 49851 5.0.1.0.0.2.ip6.arpa. GVMC0TF/hNZGCCRXY4bvpvuyqtmqC5mqhVp0DGhxldJ0m64CVzmOcFMf S3aqoggYRPMYqHNKG4Zjg40/IlwXSdsLmTmOQgBu0OBR4tJBGuomqoTP 7BsXeKx0a3Vgz/8mdz1Nf8e4czGWwkCAo/AomluyWKdEDM5bQiX30Uqa e0k= ;; Received 372 bytes from 2001:dc0:2001:a:4608::59#53(e.ip6-servers.arpa) in 373 ms 3.0.0.0.5.1.0.c.5.0.1.0.0.2.ip6.arpa. 3600 IN NS wonderland.broker.freenet6.net. ;; Received 173 bytes from 72.55.143.215#53(ns1.gogo6.com) in 125 ms 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.3.0.0.0.5.1.0.c.5.0.1.0.0.2.ip6.arpa. 3600 IN PTR wonderland.broker.freenet6.net. ;; Received 128 bytes from 2001:5c0:1400:b::9#53(wonderland.broker.freenet6.net) in 0 ms
我還嘗試了http://www.sput.nl/internet/ipv6/chkip6rev.html之類的線上工具,他們確實報告了 SERVFAIL。我等了一天,看看這是否是一些記憶體的影響,但問題仍然存在。這裡可能發生了什麼?
此委託中的某些 DNS 解析器將失敗:
3.0.0.0.5.1.0.c.5.0.1.0.0.2.ip6.arpa. 3600 IN NS wonderland.broker.freenet6.net.
DNS 伺服器
wonderland.broker.freenet6.net
只有一個 IPv6 地址:$ host wonderland.broker.freenet6.net wonderland.broker.freenet6.net has IPv6 address 2001:5c0:1400:b::9
當您這樣做時
dig
,您要求您配置的 DNS 解析器為您解析地址。如果該解析器沒有 IPv6,那麼它將無法遵循此委託,因為它無法訪問僅限 IPv6 的 DNS 伺服器。當你這樣做時,你dig +trace
會自己解決所有問題。如果您的系統有 IPv6,那麼它可以遵循整個鏈。在沒有 IPv6 的系統上,解析也會失敗。在這種情況下,問題(也是?)似乎與權威 DNS 伺服器中的錯誤有關
2001:5c0:1400:b::9
。它發送的答案不符合 DNS 標準。根據RFC 1034,原始問題必須包含在響應中。但是,您的 DNS 伺服器會發送一個空的問題部分(BIND 報告為“問題太多”,儘管從技術上講它是“問題不足”,!= 1
我猜是匹配的):Domain Name System (response) Transaction ID: 0xad20 Flags: 0x8400 Standard query response, No error Questions: 0 Answer RRs: 1 Authority RRs: 0 Additional RRs: 0 Answers 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.3.0.0.0.5.1.0.c.5.0.1.0.0.2.ip6.arpa: type PTR, class IN, wonderland.broker.freenet6.net
所以基本上你的權威 DNS 伺服器壞了,
dig
不在乎,但“真正的”DNS 解析器會……