請問各位大大~什麼是路由黑洞



贊助商連結


poiu124
2001-09-27, 12:58 PM
請問~~什麼是路由黑洞??
是怎麼發生的ㄋ??
又要怎麼解決ㄋ??
希望懂得人能POST上來??
讓我這些不懂了人能免費的上一課~~
拜託大家了

贊助商連結


conankun
2001-09-28, 03:38 AM
用search找"黑洞"吧....
或.....
http://www.pczone.com.tw/showthread.php?t=24348&highlight=%B6%C2%AC

milwater
2001-09-28, 10:23 AM
由於路由器的設定錯誤, 造成封包一直循環一直循環地,
無法正確到達目的地IP.
 
..在PCZone內, 對於這個詞的解釋確實不多.
建議你到國外Search Portal, 尋找"Black Hole Routers", 或是M$/CISCO等網站,
就可找到相關資料~

ee844548
2001-10-01, 08:37 PM
route table建立於每個router
表中會有附近如何到達別的router路徑
幾個hop
假使突然有一個router掛掉
可是二手資料沒有更新
導致照成一直loop
好像是這樣吧
最近看書看到的
如有錯誤敬請指教

segaage
2001-10-03, 11:39 PM
最初由 poiu124
請問~~什麼是路由黑洞??
是怎麼發生的ㄋ??
又要怎麼解決ㄋ??
希望懂得人能POST上來??
讓我這些不懂了人能免費的上一課~~
拜託大家了
Hi poiu124兄:
如果小弟沒記錯的話,黑洞路由和MTU有關,指的是當封包經過路由器時,假如其MTU大小大於下一段網路的最大值,又該封包被設定為不可分割,則路由器會捨棄該封包並回一錯誤訊息到來源端,如果沒送出訊息,則封包會一直被路由器捨棄,但來源端卻不知封包已遭捨棄,於是一邊一直送,另一邊一直丟,像個無底洞般,該路由器便成為黑洞路由,記得在M$的支援網頁裡有記載,編號好像是Q159211(還是Q268773?忘了,真抱歉)

bonjour
2001-10-04, 08:18 PM
In an internetwork, a black hole is a router that goes down and whose absence from the network is not detected by other routers. Packets that are forwarded to the black hole are dropped; they never reach their destination, and they give no indication to the stations sending them that this is the case—therefore, the data is lost.

Normally, a router will issue an “ICMP Destination Unreachable” message when it cannot forward a packet. However, with a black hole, these messages are not generated, so the user doesn’t know that data is being permanently lost.

If static routing is being used, a black hole persists until the affected router is brought back on line or until other static routers have their routing tables reconfigured to take the downed router into account. If dynamic routing is used, other routers soon detect the presence of the black hole and adjust their routing tables accordingly to favor other paths.

不知道是不是這個?我從微軟網路百科全書抓下來的