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i) Modify the password script to use the IPv6 address of the VPC Router or
ii) Use cloud-init which should take of using the IPv6 address of VPC Router.
In any case, whenever the wget is based on IPv4 or IPv6 (depending on the domain lookup) this is transparent to the VPC Router as long as the Apache process is listening on both addresses.
Note: According to latest document, password management is not supported by cloud-init. But, when it is available it should make sure that it supports IPv6
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The BGP routing process is installed on every VPC Router and will advertise the VPC network to the upstream gateway, thus all VPC routes will be advertised across the VPC Routers. This will eliminate neighbour IPv6 eliminate neighbor IPv6 VPC network traffic to go through the Cloud Uplink Router but directly between the VPC the VPC Routers in the same Supernet /50.
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