Linux
Fedora 12 上的 DNS 問題?wget wordpress.org 在 wget www.google.com 工作的地方失敗
我正在管理一個 Fedora 12 機器,但對網路細節還是很陌生。最近,我們伺服器上託管的一款 WordPress 應用程序已停止執行其自動更新或自動下載外掛的功能。
進一步調查,我嘗試了以下方法:
$ wget wordpress.org --2010-12-17 11:26:50-- http://wordpress.org/ Resolving wordpress.org... failed: Temporary failure in name resolution. wget: unable to resolve host address âwordpress.orgâ
然而:
$ wget www.google.com --2010-12-17 11:27:26-- http://www.google.com/ Resolving www.google.com... 74.125.226.82, 74.125.226.84, 74.125.226.80, ... Connecting to www.google.com|74.125.226.82|:80... connected. HTTP request sent, awaiting response... 302 Found Location: http://www.google.ca/ [following] --2010-12-17 11:27:26-- http://www.google.ca/ Resolving www.google.ca... 173.194.32.104 Connecting to www.google.ca|173.194.32.104|:80... connected. HTTP request sent, awaiting response... 200 OK Length: unspecified [text/html] Saving to: âindex.html.4â [ <=> ] 9,079 --.-K/s in 0.02s 2010-12-17 11:27:26 (462 KB/s) - âindex.html.4â
有趣的是:
$ ping wordpress.org PING wordpress.org (72.233.56.138) 56(84) bytes of data. 64 bytes from wordpress.org (72.233.56.138): icmp_seq=1 ttl=50 time=81.5 ms 64 bytes from wordpress.org (72.233.56.138): icmp_seq=2 ttl=50 time=67.3 ms ^C --- wordpress.org ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 1783ms rtt min/avg/max/mdev = 67.361/74.448/81.536/7.092 ms
和
$ nslookup wordpress.org Server: 192.168.2.1 Address: 192.168.2.1#53 Non-authoritative answer: Name: wordpress.org Address: 72.233.56.138 Name: wordpress.org Address: 72.233.56.139
nscd 已停止並刷新。iptables 看起來很乾淨。在這一點上,我已經用盡我有限的能力來診斷這個問題。任何人都可以建議解決路徑嗎?
開始測試:
wget wordpress.org.
最後的這個點很重要如果它不能解決問題,請執行以下操作:
cat ${HOME}/.wgetrc
env | grep -i proxy
wget --dns-timeout 1000 wordpress.org
wget --dns-timeout 1000 wordpress.org.
- 解釋 192.168.2.1 DNS 伺服器的用途是什麼?
- 顯示與記憶體、轉發(如果有)相關的 named.conf 部分。
- 您那裡有關於 wordpress.org 的任何聲明嗎?執行以下測試:
dig a wordpress.org. @ns1.mobiusltd.com.
dig a wordpress.org. @192.168.2.1
dig a wordpress.org @192.168.2.1
dig a wordpress.org @192.168.2.1
如果這不會給你答案顯示/etc/resolv.conf。
確保在 DNS 伺服器上正確設置了 named.conf 和 rndc 中的日誌記錄部分。然後根據需要觀察日誌、引發跟踪、dumpdb 記憶體。tcpdump 和 snoop 是你的朋友。祝你好運。