Load balancer troubleshooting-unable to access Web site

Source: Internet
Author: User
Tags server port

Failure Phenomena:

The server port under the load Balancer VIP can be telnet, but the URL corresponding to the port cannot be Opened.

Workaround:

Use forceproxy, and modify the Server's underlying configuration to resolve the failure

Two modes of dbind:

Enable: corresponds to the Alteon traditional 7-tier engine, after three handshake with the client, forwards the data to the Server.

Forceproxy: the corresponding is AE (acceleration engine), directly to the Client's three handshake message, to the Server.

Tip: If you turn on forceproxy, you can't use a SYN attack detection

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Enable

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Forecproxy:

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Host parameters

Net.ipv4.tcp_timestamps = 0

This option is turned on by Default. Use the Enable TCP timestamp option (RFC1323) to help measure and evaluate the RTT (round trip time), tcp_valid_rtt_meas (sk, tcp_time_stamp-tp->rx_opt.rcv_tsecr); Thus indirectly affects the RTO (timeout retransmission Time) optimization reasonable setting, as well as non-necessary retransmission detection and Judgment. And it can also be used to prevent serial number winding, below is the TCP serial number consumption reference, the GB link TCP session 17 seconds of data transmission on the energy consumption of light TCP serial number, if there is no time stamp option, The old retransmission message may occur just the current sequence number to the receiver, so the Error. But with the timestamp option, the PAWS algorithm can compare the recent timestamp and discard the re-appearing message.

Did not catch the fault message, directly with the manufacturer suggested method to solve the fault, this write is very rough, later met to Add.

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Load Balancing troubleshooting-unable to access Web site

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