See answer inline. Luis wrote: > have a T5120 machine with 4 internal disks. I want to have 4 Guest Domains + > the Control Domain. My point of conflict is the disks. > > I wanted to install the OS in a ZFS pool consisting of two stripped mirrors > and then from that pool create zvolumes to be used as boot devices by my > ldoms. > > I noticed that one cannot do that as otherwise OS complains as follows: > > # zpool status > NAME STATE READ WRITE CKSUM > rpool ONLINE 0 0 0 > mirror ONLINE 0 0 0 > c1t0d0s0 ONLINE 0 0 0 > c1t1d0s0 ONLINE 0 0 0 > > # zpool add rpool mirror c1t2d0 c1t3d0 > cannot add to 'rpool': root pool can not have multiple vdevs or separate logs > # > > Anyway then I created a new pool called ldomspool and I put those 2 disks on > that pool. > > At this point I will create two zvolumes in every disk pool so that at > the end I have 2 guest domains booting from rpool and 2 ldoms from ldomspool. > > Question #1, Is this the ldoms gets deployed commonly? I tried earlier file > based images for booting and the control domain runs out of memory and at > that point pages. I also tried SVM based boot devices but the performance > was terrible and to install OS on those guest domain took for ever. I just > want to have an idea if I'm following a weird approach or I'm fine.
It is not a very good practice to add volumes directly into rpool, it is better to preserve rpool only for the control domain. A better solution is, as you did, to create another zpool and to create volumes for each domain in that zpool. An even better solution is to create one zpool per domain but you need to have enough disks available. For performances, ensure that you have patch 139562-02 installed in all domains. > Question #2. When one uses ZFS one needs more memory in the machines than > usual as ZFS loves memory. In my control domain I'm assigning 5GB of RAM > just to have ZFS happy. Now if I install OS in the Guest Domains I imagine > I will need again extra memory if I go with ZFS based root. What are you > doing in this case? Are you doing ZFS based boot in guest domains or you > go for regular UFS based boot and save the extra memory? Problem is that > if you go with UFS you lose all the cool ZFS stuff. ZFS shouldn't consume that much memory anymore (since S10U5 if I remember correctly). However ZFS will take advantage of memory available to cache data, so it can use more memory but only if that memory is available. alex.
