Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Hello, I haven't really used DRBD, but I've read all the documentation I was able to find on the internet. However, there was one question that I didn't get good answer to: how (and if) DRBD is able to handle storage with 'write cache' turned on? What happens if one node dies, and the data that disc reported as 'written' isn't actually written? When the node is restarted, does it somehow know that it actually needs full sync (because the data in the disc's cache may not be actually written)? Or is it actually able to do partial sync thanks to the internal log so it knows what was really written? AFAIK for the latter, you need to be sure that the data, even though maybe not actually written to disc, would be written in correct order (so that the counters and consistency flags are updated AFTER the other writes to the disc). Is my assumptions correct? If so, is DRBD somehow able to enforce ordered writes? (Using write barriers or something?) E.g short question: may I use write cache on both nodes and not worry about data integrity (that is - until two of them die at the same time...) Thanks!