gtpc_ltd wrote:
Sonicwall end
https://cru-technologies.co.uk/wp-content/uploads/2020/10/log_463FBC_10-22.csv

The Sonicwall eventually says "IKE negotiation aborted due to Timeout"
The Vigor says "IKE link timeout: state linking"

These two boxes are not coming to an agreement, as to what to use ...

The Draytek page is somewhat out of date.
So I have different options on the 2862 (FW 3.9.3)
So the Draytek - dial out settings - guide just shows IPSec Tunnel - on the 2862 I have IPSec Tunnel - but then options IKEv1, IKEv2, IKEv2 eAP, Xauth.
On the Ipsec security method, advanced, the options are grouped on the guide, but separate on the 2862 - but they are matched.
I have updated to be letter for letter the guide

Still won't connect.
I hate sonicwalls.

When my 2860 dials my 2830, the next message after the "IKE ==>, Next Payload=ISAKMP_NEXT_SA, Exchange Type = 0x2, Message ID = 0x0"

is one that says: "Accept Phase 1 prorosals : ENCR OAKLEY_AES_CBC, HASH OAKLEY_MD5" (spelling mistake has been there years )
then the rest of the negotation.

Yours stops dead (timeouts) - so it either gets nothing back from the sonicwall, or something it doesn't like/expect. (I don't know exactly, what the message would say for 3DES)

(So it fails at the first hurdle )

So a packet monitor on the SW shows ;
37 10/22/2020 04:32:04.496 X1*(i) -- 31.10.**.** 78.32.**.** PPPOE-SES IP 500,500 CONSUMED 254[254]
Comsumed? That doesn't sound good.

Something from Wikipedia ...

The IKE specifications were open to a significant degree of interpretation, bordering on design faults (Dead-Peer-Detection being a case in point[citation needed]), giving rise to different IKE implementations not being able to create an agreed-upon security association at all for many combinations of options, however correctly configured they might appear at either end.

Is IKE V2 an option? (I've never used it)