上午11:23左右,在公司无法访问百度,开始我还怀疑是公司网络(网通线路)的问题,后来在BBS上看到还有其他地区的网通用户也都无法访问百度。
后来获知,百度服务器托管的中国网通土城IDC机房发生故障,百度的网通服务器全部无法访问。托管在该机房的大型网站还有搜狐、TOM、九城。我用Linux的dig命令查询出百度的网通IP──202.108.22.5、202.108.22.43,直接访问IP也无法打开:
20多分钟后,百度恢复正常。我再次dig一下www.baidu.com,发现域名已经解析到220.181.37.4、220.181.38.4这两个电信的IP上:
百度在DNS服务器更改域名A记录后,几分钟后理应可以生效。但是域名的TTL记录设置了缓存的时间,在这个时间内,如果需要重新解析域名,会直接从用户本地的缓存读取,而不是直接向DNS服务器请求。这样就导致了在百度网通机房发生故障的那段时间内,访问过百度的网通用户在百度切换域名后的一段时间内仍然无法访问。
上周,我部署过一组的服务器,可以像百度一样进行电信、网通线路互相切换的容灾处理。但电信切到网通,网通切到电信,必将导致其中一方用户的访问速度变慢,所以只是解决故障的权宜之计。等我们部门本季度的服务器采购到位后,我们将部署北京电信与外地电信,北京网通与外地网通之间的冗余互备。
后来获知,百度服务器托管的中国网通土城IDC机房发生故障,百度的网通服务器全部无法访问。托管在该机房的大型网站还有搜狐、TOM、九城。我用Linux的dig命令查询出百度的网通IP──202.108.22.5、202.108.22.43,直接访问IP也无法打开:
引用
[root@zhangyan4 zhangyan4]# dig www.baidu.com
;; ANSWER SECTION:
www.baidu.com. 84 IN CNAME www.a.shifen.com.
www.a.shifen.com. 303 IN A 202.108.22.5
www.a.shifen.com. 303 IN A 202.108.22.43
;; ANSWER SECTION:
www.baidu.com. 84 IN CNAME www.a.shifen.com.
www.a.shifen.com. 303 IN A 202.108.22.5
www.a.shifen.com. 303 IN A 202.108.22.43
20多分钟后,百度恢复正常。我再次dig一下www.baidu.com,发现域名已经解析到220.181.37.4、220.181.38.4这两个电信的IP上:
引用
[root@zhangyan4 zhangyan4]# dig www.baidu.com
;; ANSWER SECTION:
www.baidu.com. 129 IN CNAME www.a.shifen.com.
www.a.shifen.com. 356 IN A 220.181.37.4
www.a.shifen.com. 356 IN A 220.181.38.4
;; ANSWER SECTION:
www.baidu.com. 129 IN CNAME www.a.shifen.com.
www.a.shifen.com. 356 IN A 220.181.37.4
www.a.shifen.com. 356 IN A 220.181.38.4
百度在DNS服务器更改域名A记录后,几分钟后理应可以生效。但是域名的TTL记录设置了缓存的时间,在这个时间内,如果需要重新解析域名,会直接从用户本地的缓存读取,而不是直接向DNS服务器请求。这样就导致了在百度网通机房发生故障的那段时间内,访问过百度的网通用户在百度切换域名后的一段时间内仍然无法访问。
上周,我部署过一组的服务器,可以像百度一样进行电信、网通线路互相切换的容灾处理。但电信切到网通,网通切到电信,必将导致其中一方用户的访问速度变慢,所以只是解决故障的权宜之计。等我们部门本季度的服务器采购到位后,我们将部署北京电信与外地电信,北京网通与外地网通之间的冗余互备。
Coach Outlet Online
2012-5-19 16:50
At the Coach Outlet Online Store, quality products and satisfying service are provided;High safety and prompt delivery is guaranteed.Coach Outlet has always been simple,durable style features to win consumers.The products are more flexible,with easy bleaching,wear characteristics,and simply use a damp cloth.
Christian Louboutin
2012-5-19 17:35
christian louboutin have own characteristic designs. The beautiful crystals have added the magical finishing touch to countless bridal gowns. Just get some for yourself. The first Men's Boutique, christian louboutin uk Boutique Homme on Rue Jean-Jacques Rousseau in Paris, opened in the summer of 2012.
Louis Vuitton UK
2012-5-19 17:35
Cheap louis vuitton uk wholesale offers a variety of options to satisfy your needs. Some new ones even has fashionable styles fold over flap to disguise the snap closure and a draw string is added for a convenient closure. Louis vuitton outlet online just like a person who want to show himself in front of other people, because he is confident enough, he can attain the respect of other people.
CoachOutlet
2012-5-19 17:35
coach outlet has become a popular shopping experience for consumers around the world, and a desirable distribution channel for manufacturer's and retailers. Coach outlet online develops very quickly because it runs by its own special way and it contents the customers greatly.
Air Jordan
2012-5-19 17:36
Thank you for shopping in our store. We are a reliable online jordan bags seller, specialist in providing numbers of new air jordan bags at amazing price . If you need practical, fashionable and well-known nike dunks, you can consider to choosing on the nike Outlet. Its nice and popular design will make you feel a sense of fresh air.
Nike Air Max
2012-5-19 17:36
This nike air max for sale belongs to the sounding just what are termed as nike air vintage best sellers, many other products and services for the reason that range appearing companies the actual nike air Galliera, plus the nike air outlet monogram selection. nike dunks are made of high leather materials which can be durable and fashionable.They will make you become the focus in the streets or audience.
xujie123
2012-5-21 11:02
Our online store offers you discounted Designer louis vuitton replica wallet at present. You could find them in desirable quality and price. If you don't mind high class louis vuitton uk, have a good time here.louis vuitton Store Online Handbags can also bring great accuracy as well as practical applicability and fashionable.Have you ever dreamed of being as charming as Madonna? Have you ever thought of becoming an envy of all your friends? If so, come to louis vuitton outlet.<br/>
xujie555
2012-5-21 13:24
coach factory outlet uses graceful accessories to match the classical logo of coach, which is the best combination of coach. The handmade coach products?can make you more charming and graceful.coach factory online provides people many coach goods. If you wish to snatch the coach handbag, then this best method is made for that you like for coach discount.coach factory outlet online is a fashion brand to ensure its quality. With designer coach shoulder bags, you will always attract people's attention. The bags will emphasize your personal style and taste.<br/>
xujie333
2012-5-21 14:47
coach outlet online Store guarantee that all the coach handbags offered are own high quality. In addition , all of them are sold at an unexpected low price.If you want to purchase, just visit their website.coach factory outlet is really sizzling kinds of shopping way for you. With the usage of the replica designer coach bags, you can surely be able to change your individual looks in a stunning manner.Coach bags on sale from the coach outlet are cheap or discount prices that you certainly will stand out from the crowd on your next camping trip!<br/>
coach88888888
2012-8-13 17:33
If you desire to go to Coach Factory Outlet, but have no idea in which to go, you can research online. It is no doubt that there is drastically information and details about it for the reference.Coach Factory Online are loved by many people, when you walk in the street, you could see many people take coach styles.hat experts claim Coach Outlet Online shopping is in the changes they are available in.Coach Outlet will send you a coupon in the post to use in their upon only after you type a achieve. The Coach bags are customarily somewhat many than the ones in the stores.
FGF
2012-9-26 11:12
while you put on this sort Karen Millen sale of shoe, you will discover just a little portion of your large toe as nicely as the next finger is noticeable thus displaying a glimpse. Peep toe is good for cozy and mild weathers. with the summer/spring collection, the designers allow it to be a place to show at the least a single type of peep toe shoes. They do this since these footwear are often in need within the style shoes Karen Millen UK market.dark peep toe footwear certainly are a craze amongst females since of the universal appeal and all climate usage. These footwear could possibly be complemented with shorts and skirts in summer, and leggings and sweater attire in winter. dark shade complements nicely with all attire patterns and shades and therefore is commonly a obligatory foot put on selection for ladies.Black Karen Millen dresses footwear are available in fascinating styles and categories. They could possibly be heeled, flats, sandals, and jellies.
Karen Millen dresses
2013-1-31 10:29
if your Karen Millen dresses outfits do not fit you can send it and have the correct dimension. If you go to the variety store if you notice how the clothesin larger sizes items are thus costly. The fantastic thing about purchasing on the web is you will put away much cash! Even with Karen Millen transport you are still saving money when compared to the high-priced stores. Buying Karen Millen coats full figured ladies clothes are difficult to do throughout shops and it is costly. I hope looking at this post you understand the most important advantages for you to Karen Millen sale order online for your clothesin larger sizes requirements.Corroded, our own ridiculous pet is sporting yet another brand-new bandanna, that he wears on a regular basis from the garden and individuals are always ending us all on each of our taking walks, declaring exactly how neat as well as pretty they seems to be. Must take following us, hey. This started out being a joke as none of us recognized what things to provide your ex again as a present from holiday. Right now each time a friend disappears altogether, again comes an additional bandanna, with every person wanting to out and about carry out the other,
HAWERE
2013-3-8 17:20
买轴承就到:www.jkzhoucheng.cn
gclub
2022-3-19 05:29
gclub my children to study at this university. will bring my King99 university and very good educationhttps://www.king99step.net/gclub/ https://www.king99step.net/
shz
2022-7-23 15:18
Very interesting blog. Alot of blogs I see these days don't really provide anything that I'm interested in, but I'm most definately interested in this one. Just thought that I would post and let you know. Scam Risk
shz
2022-7-23 15:23
I am hoping the same best effort from you in the future as well. In fact your creative writing skills has inspired me. Scam Risk
shz
2022-7-23 15:32
Actually I read it yesterday but I had some thoughts about it and today I wanted to read it again because it is very well written. Scam Risk
shz
2022-7-23 15:43
Took me time to understand all of the comments, but I seriously enjoyed the write-up. It proved being really helpful to me and Im positive to all of the commenters right here! Its constantly nice when you can not only be informed, but also entertained! I am certain you had enjoyable writing this write-up. Scam Risk
szz
2022-7-23 15:45
I like viewing web sites which comprehend the price of delivering the excellent useful resource free of charge. I truly adored reading your posting. Thank you! Lead generation
shz
2022-7-23 15:48
New site is solid. A debt of gratitude is in order for the colossal exertion. Scam Risk
分页: 2/3 1 2 3