How to generate SegWit address How do I generate a SegWit address using Bitcoin Core CLI? Also will I be able to redeem those outputs and send them to a "legacy" address? If so, will this second transaction be accepted by older, non-SegWit clients?
How do I generate a SegWit address using Bitcoin Core CLI?


You can use addwitnessaddress addr, where addr is an existing P2PKH or P2SH address of yours. It will construct a P2SH-P2WPKH or P2SH-P2WSH address with the same key/script, if known to be valid.

Note that this command is not available until SegWit is active on the network, as before that time, such outputs would be spendable by everyone.

Since Bitcoin Core v0.16.0, P2SH-P2WPKH addresses are the default, and the addwitnessaddress RPC is deprecated.


  Also will I be able to redeem those outputs and send them to a "legacy" address?


Yes.


  If so, will this second transaction be accepted by older, non-SegWit clients?


Yes, it is a softfork. Every new transaction is valid according to the old rule. If not, a chain split would occur. Older clients may not see the transaction until it is confirmed, however.