Client Certificate Authentication not working through LTM

what client authentication settings have you got on the client ssl profile? I imagine Request would be the best fit here because it will attempt client cert auth if there's a cert available on the client but won't enforce it if there isn't one. Your backend could then deal with the basic auth. Just a thought.

Also, could this feature help instead? Proxy SSL Feature. That way ther server itself does the authenticating.

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