With the XRAID the big news was the increase in capacity to 3.5TB through the addition of bigger drive modules. What is even better is that Apple now fully supports the use of a fibre switch to split this storage into logical volumes called slices that can be used independently by different machines at the same time. The best news of all was the fact that Apple now supports these machines coming from different vendors, with the certification of the XRAID by 11 different vendors including Red Hat and Microsoft.
Given the relatively cheap per-gigabyte storage the XRAID offers, this final change means that Apple will suddenly appear on the radar of companies that wouldn't have even considered using Apple hardware before.
Turning to the new Xserves, they look on paper to be impressive machines. This is because of the simple fact that Apple has managed to shoehorn two of the hot-running 2GHz G5 processors into a 1U high case. This is made partly possible because the machines are using G5s built using IBM's new 90nm process. These chips use significantly less power and hence produce less heat that needs to be dissipated than the 130nm-sized ones used in the regular models.
The other part of the equation is the impressive cooling system which uses eight fans and sacrifices a drive bay on the front of the machine to ensure good air flow. I haven't heard the new model running yet, but considering that the old Xserve acquired the nickname of "Windy" in many an installation, users in the future may be very shortly referring to files stored on "Hurricane Xserve".
The technical overview document Apple posted on its website for the Xserves suggests there is a lot more to this new model than simply the addition of the G5.
For a start, the new models finally have the ability to use PC3200 EEC RAM. The lack of this feature in previous models meant that big customers like Virginia Tech, which built the world's third-fastest supercomputer using 1100 G5s, had to write custom software to attempt to catch any randomly changed bits in a data set. Where this was not possible they resigned themselves to running computations more than once to catch changes. Obviously this was far from ideal, so nobody was surprised when it was reported that they will be upgrading to Xserve G5s in the coming months.
Given that the Xserve is based on the Power Macintosh G5, it is not surprising that it now shares the ability to have 8GB of RAM along with 250GB SATA drives modules on individual 150MB/s buses. However, what is good news is that the Xserve now supports the addition of a hardware RAID controller to provide up to half a terrabyte of RAID 5-based storage. The only disappointing thing is that these new SATA drives only operate at 7200rpm instead 10,000rpm, which would provide better seek times.
From a support angle as well Apple is stepping up to the plate, in the US at least, with AppleCare plans for both software and hardware that guarantees quicker response times. Unfortunately, reports from the web have indicated that in a number of cases the response has been less than stellar.
To be fair to Apple, from initial inspection it appears that in most documented cases the issue seems to be with the resellers who are contracted to deliver on these support contracts. The most common problem seems to be that the reseller wasn't holding Xserve spares. In another instance a reseller's engineer didn't have access to transport to service a broken Xserve and so had to come via train -- leaving the customer without a server for two days. Obviously the lesson here is to make sure before you buy one of these machines and a support contract that somebody local can actually deliver on the contracts promises.
More disturbing, though, are the reports of software issues not being attended to in a timely manner. In one reported case on the Macintouch website, Frank Durda uncovered an issue with Mac OS X Server 10.3 on an Xserve that causes kernel panics every few hours if NFS is used. Two months after this issue was uncovered the only solution Apple had for the user was to downgrade to Mac OS X Server 10.2.8. Given that 10.3 fixes a whole bunch of other issues, having to downgrade to 10.2.8 is obviously not a good solution.
At the end of the day, for an enterprise user to choose an Apple solution for their core network they have to be not only confident that the hardware and software combination meets their needs, but that in the event of a problem support will be available to get them back up within the shortest possible time. While Apple is learning fast about the needs of this market and responding with new models like the Xserve G5, it needs to be able to provide top-notch support or it will find its computers relegated to the role of file server for the graphics department.