The trick is to find a common baseline format, like CSV or JSON, then you can leverage the bazillion of existing tools.
The second trick is to split the data in manageable chunks (a day of logs for example), then you can transfer one unit at a time to the new system.
Dump a chunk on one side, load on the other side, verify it's good. It will still take a while but you have a good indication of progress and don't need to start all over if one chunk fails.
The second trick is to split the data in manageable chunks (a day of logs for example), then you can transfer one unit at a time to the new system.
Dump a chunk on one side, load on the other side, verify it's good. It will still take a while but you have a good indication of progress and don't need to start all over if one chunk fails.