代理上網奇怪的問題,squid
squid代理最近出現這樣的問題:
在伺服器里能解析域名,但是在客戶端就是上不了網,具體的提示有:
The requested URL could not be retrieved
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While trying to retrieve the URL: http://www.baidu.com/
The following error was encountered:
Unable to determine IP address from host name for www.baidu.com
The dnsserver returned:
Temporary network problem, please retry later
This means that:
The cache was not able to resolve the hostname presented in the URL.
Check if the address is correct.
Your cache administrator is 84771409(77314).
--------------------------------------------------------------------------------
Generated Wed, 27 Aug 2008 03:29:30 GMT by Panyu-proxy (squid/2.5.STABLE14)
在伺服器里查看日誌 cat /var/log/squid/cache.log
提示如下:
2008/08/27 11:30:22| dnsSubmit: queue overload, rejecting tg4a31.mail.163.com
我查看dns進程的確有很多,kill一些dns進程后,可以上網了，但是這個不是解決問題的最終辦法,請問各位高手,如何解決這個問題呢?
《解決方案》
如果是dns請求超載的話cache.log中應該有如下兩句
2008/08/14 11:44:03| WARNING: All dnsserver processes are busy.
2008/08/14 11:44:03| Consider increasing the number of dnsserver processes to at least 288 in your config file.
上邊是我的伺服器在14日發生的超載日誌，當天突然出現大量dns請求，上邊的日誌最少要設置288個dns服務線程，平時我用64個滿足了，實際到後來我增加到400+才不超載了。
修改squid.conf
dns_children 64
調整dns服務線程數
《解決方案》
還有個問題，就是首頁能打開，確認不是緩存中的。下面的鏈接就打不開，提示的內容也是同樣的。
我打開www.sohu.com后，點擊「新聞」后
The requested URL could not be retrieved
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While trying to retrieve the URL: http://news.sohu.com/
The following error was encountered:
Unable to determine IP address from host name for www.baidu.com
The dnsserver returned:
Temporary network problem, please retry later
This means that:
The cache was not able to resolve the hostname presented in the URL.
Check if the address is correct.
Your cache administrator is 84771409(77314).
《解決方案》
這個應該不是每個客戶端都出現的問題，有可能是baidu插件的原因，換一台乾淨的客戶端計算機試試。
《解決方案》
按2樓的方法先查下吧，多數是dns_children參數過小造成的，按我以前做過的經驗，兩台squid供800人上網，每天dns_children我設置在150
