In the past I have used Veritas Cluster Server for HA clusters of Sybase and other databases at large financial institutions.
Now I am going to have locally written processes that could benefit from some similar behavior. e.g. "fail onto this machine if this process fails"
We will have VCS in the environment for various databases, so the overall skill set is not an issue; but this specific aspect.
Have you used VCS for custom application deployments? Was it worth it? Did it buy you much?
vxprint -m -g command in vxvm give lot of inofrmation about the volume like rid , pub offsets etc. Is there a command in solaris volume manager to get the such information?
and vxprint -F %len -g -v gives volume length in blocks. Is there any command in solaris volume manager to get length information?
We're a Solaris shop looking at RedHat Enterprise Linux and one of the things we're wondering is if we should keep Veritas Volume Manager + FileSystem or go with LVM+ext3 or RedHat's preferred cluster filesystem solution, GFS.
One of the things we like about Veritas is that it can use Veritas Volume Replicator to have a remote copy of important filesystems. This functionality seems to be missing from RedHat, DRBD doesn't seem to be packaged in RHEL...
So my questions are:
We're a site with over 100 servers and we're considering a switch from traditional file-level backups (using Netbackup) to block-level (using Acronis). Of course, with this, we're also considering a switch from the traditional tape based system (using a tape-library) to performing backups to disk.
I would like to know if anyone has done a similar switch (specially between these 2 products) and if so, what are your experiences?
As a final note, I want to mention that what grabbed my attention from Acronis is its ability to perform ONLINE image-backups as well as INCREMENTAL image-backups. I'm a little bit skeptic about performing ONLINE image-backups as I have always performed them on COLD systems in the past. I haven't properly test the product but will be pretty soon.
Thanks !
How can this be?
Running a cp or rsync (with -W --inplace) takes two hours for 93Gb; a tape restore over the dedicated backup network is 41 minutes. Tape restore is 50 Mb/s; disk to disk was measured and calculated to be 16 Mb/s tops - 2 Mb/s if the CPU is busy.
The restore software is Veritas NetBackup; the disks are on an EMC Symmetrix array over fiber. The box is an HP rx6600 (Itanium) with 16 Gb running HP-UX 11i v2. All the disks are on one fiber card, listed as:
HP AD194-60001 PCI/PCI-X Fibre Channel 2-port 4Gb FC/2-port 1000B-T Combo Adapter (FC Port 1)
The disks are also all using Veritas Volume Manager (instead of HP LVM).
Update: It occurs to me that this is not just a straight disk-to-disk copy; in reality, it is a snapshot to disk copy. Could reading the snapshot be slowing things down that much? The snapshot is an HP VxFS snapshot (not a vxsnap); perhaps the interaction between the snapshot and VxVM is causing speed degradation?
Update: Using fstyp -v, it appears that the block size (f_bsize) is 8192; the default UNIX block size is 512 (or 8192/16). When testing with dd, I used a block size of 1024k (or 1048576, or 8192*128).
I really wonder if it is the block size. I read over at PerlMonks that the Perl module File::Copy is faster than cp; that is intriguing: I wonder.
If NetBackup is using tar, then it is not using cp: that might explain the speed increase as well.
Update: It appears that reading from snapshot is almost twice as slow as reading from the actual device. Running cp is slow, as is tar writing to the command line. Using tar is slightly better (when using a file) but is limited to 8Gb files (file in question is 96Gb or so). Using perl's File::Copy with a non-snapshot volume seems to be one of the fastest ways to go.
I'm going to try that and will report here what I get.