problem with "Rational Build Forge" engine could not connect to build forge from RTC

Dear All,

I am writing to seek your help.

RTC:  3.0.1

BuildForge:  7.1.2

We encountered a problem today. The problem is RTC could not connect to BuildForge with the error message below:

com.ibm.team.repository.common.transport.TeamServiceException - CRJAZ0099I when access to  URL“https://oprtc:9443/ccm/service/com.ibm.rational.connector.buildforge.internal.common.IBuildForgeServicesLayerService”时，发生以下 HTTP 错误：“java.net.SocketTimeoutException”

I created a "Rational Build Forge Engine" and tested connection successfully some days before.

But today, this build engine could not connect to BF server.

I am sure the BF ip(99.1.36.124) and port number(3966) and build forge user id are all correct.

I telnet from RTC Server - telnet  99.1.36.124  3966 and the connection is ok.

Checked "active services" from ccm admin console, I  can see there are several buildforge related services and hung there. Not sure why?

The hung services are as below: They alreay run for more than 3 hours but still there.

com.ibm.rational.buildforge.team.internal.service.BuildForgeServicesLayerService.requestConnectionTest

com.ibm.rational.buildforge.team.internal.service.BuildForgeEventPollerScheduledTask.executeTask

Could anybody help to have a look?

Thank you very much!

Thanks&Best regards,

Richar Cai