Took the SP Lab in RTP yesterday and things did not go well.
First off at the very start of the exam was a troubleshooting step to get some IGP working. I fixed up obvious errors but ran into two XR (GSR) subif's that would not form IGP adjacency. Looking at the problem it appeared to be a one way communications problem. After verifying the link on XR and double checking the switch ports, etc, I still could not get this IGP adjacency to form. When I attempted to ping the XR routers own IP address on the interfaces, there was no response. Bell goes off.. I *could* ping adjacent routers on the same subnet from XR, but other devices on the subnet could NOT ping XR. It seemed to be some one way issue with the control plane. In an attempt to try and fix it and move on, I tried deleting the interface in XR and completely re-adding it with the sub-ifs. NOTHING. Finally at my wits end I had to get the protor involved. After about 10 minutes of trying to convince him it was a hardware issue, he agreed and had to reboot the XR router. 30-40 minutes later, XR comes up... all is fine! Pardon, but WTF!? This ended up costing me about 90+ minutes as I really could not continue without getting the core IGP network up and this router was one of my RR to make everything work. Really disappointed in this experience. The proctor allowed me more time (only about 30 minutes), but I was already far to far behind and very frustrated at this point. Everything from there on out was a blitz for time where I just tried to get parts working that I could quickly.
So, learn from my bad experience. If you have an XR router involved (maybe GSR specifically) and for some reason the link is up, but you cannot ping the routers own interfaces, get the proctor and walk out the door until the thing is fixed. If you stick around and wait for the thing to be fixed, the most you get is half hour. I believe if you get up and walk away you will get the full time for them to fix the problem. Either way, I think it's BS! You would think they would double check these things before the lab goes live. (especially since they admited it was a rare, but known issue).
Other than that, my impressions of the lab seemed fair. The testing topics were spot on for the most part. However a I do have a question. With all of the devices preconfigured (with sutff to be fixed) what is the general rule of thumb about changing pre-configured parts. My thought was always unless the question specifically tells you YOU CANNOT change things or use things, it's fair game. I've read elsewhere that the rule of thumb is that you can't change any preconfiguration unless it's an obvious error to get things working. Thoughts?