Troubleshooting - Revision history

Wensong: /* UDP service fail over */

2007-03-11T14:54:33Z

‎UDP service fail over

2007-03-07T15:33:49Z

‎Troubleshooting Examples

2007-02-01T15:43:34Z

‎Real Server

2006-11-11T04:01:04Z

2006-10-17T13:36:16Z

‎Introduction

2006-08-02T14:50:04Z

2006-05-28T01:06:20Z

‎Troubleshooting Examples

2006-05-07T12:54:58Z

2006-05-07T05:17:23Z

‎Real Server

2006-05-07T05:13:20Z

‎Load Balancer

← Older revision		Revision as of 14:54, 11 March 2007
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	: Hello, I have a two directors in high availability configuration. All it's OK for TCP, but for UDP it's no OK. In UDP load balance it's ok, but the fail over don't happens. If one client is "redirected" to one real server, the connections are redirected always to this server, even the server goes down.		: Hello, I have a two directors in high availability configuration. All it's OK for TCP, but for UDP it's no OK. In UDP load balance it's ok, but the fail over don't happens. If one client is "redirected" to one real server, the connections are redirected always to this server, even the server goes down.
		+
		+	First, check if the monitoring program works for UDP service, and make sure that it can remove the server from the scheduling list when its UDP service is down. Second, if the client uses the fixed port to access UDP service, do not use the quiescent option to setup server weight zero when server goes down. It's because that all the packets from this client will be continuously sent to a dead server when its server weight is zero.

	=== lvs-kiss ===		=== lvs-kiss ===

← Older revision		Revision as of 15:33, 7 March 2007
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	== Troubleshooting Examples ==		== Troubleshooting Examples ==
		+
		+	=== UDP service fail over ===
		+
		+	: Hello, I have a two directors in high availability configuration. All it's OK for TCP, but for UDP it's no OK. In UDP load balance it's ok, but the fail over don't happens. If one client is "redirected" to one real server, the connections are redirected always to this server, even the server goes down.

	=== lvs-kiss ===		=== lvs-kiss ===

← Older revision		Revision as of 15:43, 1 February 2007
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	Capture all the packets related to virtual service at real servers, and check whether request packets are received and response packets are sent out correctly.		Capture all the packets related to virtual service at real servers, and check whether request packets are received and response packets are sent out correctly.
		+
		+	In the [[LVS/DR]] and [[LVS/TUN]] clusters, we may need to pay attention to [[ARP Issues in LVS/DR and LVS/TUN Clusters\|ARP issue]]. We can also capture ARP packets at [[real server]] and make sure that ARP works correctly.

	== Troubleshooting Examples ==		== Troubleshooting Examples ==

← Older revision		Revision as of 04:01, 11 November 2006
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	* [http://www.ssi.bg/~ja/L4-NAT-HOWTO.txt LVS-NAT troubleshooting HOWTO from Julian]		* [http://www.ssi.bg/~ja/L4-NAT-HOWTO.txt LVS-NAT troubleshooting HOWTO from Julian]
	* [http://www.ssi.bg/~ja/TUN-HOWTO.txt LVS-TUN troubleshooting HOWTO from Julian]		* [http://www.ssi.bg/~ja/TUN-HOWTO.txt LVS-TUN troubleshooting HOWTO from Julian]
		+
		+	[[Category:LVS Handbook]]

@@ Line 8: / Line 8: @@
 * [[LVS/DR | Virtual Server via Direct Routing]]
-Then, we can use some packet capture tools, such as [[ethereal]] and [[tcpdump]], to do troubleshooting at our cluster system. First, we can capture the load balanced traffic at both [[load balancer]] and real servers, in order to make sure that basic load balancing system works; Second, we can also capture packets of service monitoring among load balancers and real servers, to verify that cluster monitoring and high availability works as expected.
+Then, we can use some packet capture tools, such as [[ethereal]] and [[tcpdump]], to do troubleshooting at our cluster system. First, we can capture the load balanced traffic at both [[load balancer]] and [[real server]]s, in order to make sure that basic load balancing system works; Second, we can also capture packets of service monitoring among [[load balancer]]s and [[real server]]s, to verify that cluster monitoring and high availability work as expected.
 == Load Balancer ==

← Older revision		Revision as of 14:50, 2 August 2006
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	If you compile linux without the CONFIG_IP_VS_PROTO_TCP configure option, ipvsadm does not give any error messages, but does not grab incoming connections.		If you compile linux without the CONFIG_IP_VS_PROTO_TCP configure option, ipvsadm does not give any error messages, but does not grab incoming connections.
		+
		+	== External Links ==
		+
		+	* [http://www.ssi.bg/~ja/L4-NAT-HOWTO.txt LVS-NAT troubleshooting HOWTO from Julian]
		+	* [http://www.ssi.bg/~ja/TUN-HOWTO.txt LVS-TUN troubleshooting HOWTO from Julian]

← Older revision		Revision as of 01:06, 28 May 2006
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	== Troubleshooting Examples ==		== Troubleshooting Examples ==
		+
		+	=== lvs-kiss ===

	While LVS provides basic means for load-balancing, [[lvs-kiss]] provides some more sophisticated possibilities.		While LVS provides basic means for load-balancing, [[lvs-kiss]] provides some more sophisticated possibilities.

@@ Line 12: / Line 12: @@
 == Load Balancer ==
-Capture all the packets related to virtual service, and check whether request packets are received at the load balancer, and forwarded to real servers correctly.
+Capture all the packets related to virtual service, and check whether request packets are received at the [[load balancer]], and forwarded to real servers correctly.
 == Real Server ==
-Capture all the packets related to virtual service at real servers, and check whether request packets are received and response packets are sent correctly.
+Capture all the packets related to virtual service at real servers, and check whether request packets are received and response packets are sent out correctly.
 == Troubleshooting Examples ==

← Older revision		Revision as of 05:17, 7 May 2006
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	== Real Server ==		== Real Server ==
		+
		+	Capture all the packets related to virtual service at real servers, and check whether request packets are received and response packets are sent correctly.

	== Troubleshooting Examples ==		== Troubleshooting Examples ==

← Older revision		Revision as of 05:13, 7 May 2006
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	== Load Balancer ==		== Load Balancer ==
		+
		+	Capture all the packets related to virtual service, and check whether request packets are received at the load balancer, and forwarded to real servers correctly.

	== Real Server ==		== Real Server ==