On-line LVS load Balancer request does not forward case simple solution analysis one case

The structure of an online architecture is basically as follows:

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Basic Schema Description:

The front-end uses lvs+keepalived to do load balancing and high availability to forward the client's request to the backend Business Server, which is the 4 set of Nginx+tomcat business servers. To be more straightforward, those nginx+tomcat can simply be understood as LVS clients.

Fault Description:

When LVS forwards to 58.2.12.20 this server, the value of Activeconn also some, inactconn almost no value. In order to this problem tangled for a few days delay, because just to the company can not solve these problems oh.

Solution Ideas:

1) The first is to determine whether the back end of the realserver can be normal access, the results of one-to-one debugging access, no problem found.

2) View keepalived.conf also found no problems

3) View the VIP of each realserver can also get to, even later write their own script to the LVS server to regain, and found that no different, also can get to VIP address, prove this VIP configuration no problem;

4) Contact the operation of the whole friends, asked a few remote also did not see what is the specific problem, I am depressed oh.

5) The elimination method, since some LVS client, that is Realserver (nginx+tomcat), then compare these normal forwarding Nginx configuration file (that is, the LVS client configuration file, Nginx this piece to start), Then download to the local Windows system, and another nginx configuration file that cannot be forwarded is compared with Beyond Compare 3. Found a major problem. Where the abnormal can be forwarded is not in the Nginx configuration file, as follows

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Can not forward the Nginx configuration file inside, directly write dead to use eth0 to handle customer requests, that is, to directly deal with the LVS service side thrown over the request.

Solution: Directly to the Nginx listen listening IP address using SED to replace the empty, and then save, restart Nginx.

Observe again:

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As you can see, it's OK.

Because the collation of the relatively hasty, what is not in place, but also ask you a lot of guidance. A lot of criticism. It is hereby recorded and kept as a memo.

Herd 2015 07 10

This article from "The Herd-Han Yanwei-Yun Road" blog, declined reprint!

On-line LVS load Balancer request does not forward case simple solution analysis one case