Continuing disrupted file transfer: magic of dd and netcat
We had a problem last week. DBA team wanted to clone QA database from the export backup of production database. A usual activity in DBA world, I guess. Our production and qa systems are at different sites and we were facing some WAN issues resulting in very slow file transfer. Export backup consisted of one file of size 3.8 GB. Our offshore DBA started file transfer at 3 AM EDT. By 8 PM in the evening, almost 3.3 GB had been copied. I know it's a long long time. But, WAN was really slow because of some third-party issues. And just then network team started working on the issue (with no prior notification to us of course). You can imagine what would have happened after that. Yes, connection was broken and solaris 8 ftp server doesn't support 'restart'. Knowing that ftp copies file sequentially, I was pretty much confident that there must be some way to continue with that 3.3 GB file. My acquaintance with dd and nc came to rescue. This is how I did it- Problem: There is a