To share what I've learned !

Before dive into the lessons learned, have to set the stage where I've gathered this information.  Past 10+ years I've consulting multiple large scale SP networks and executed complex DC migrations.  These lessons captured when I failed to notice something and to enforce in the future activities. As the title of this blog have to share what I've learned to a wider audience. Some are well-known fact but keeping a note will help to do a quick check before each meeting. I'll divide it into three parts will follow up with 1.        Don't expect customer knows his/her network: This is especially true in large SP networks; There may be multiple reasons I've seen few widely; components added to patch temporary, stay lifelong and people tend to forget it.  Added functionality no more used and people around that already left the company.  Therefore don't take everything customer says 100% true there is always surprise waits for you. If possible try to do your