I ran across an issue today that my various sources of troubleshooting (ok, Google) couldn’t help solve – at least not directly. I configured SnapMirror between two disparate systems for a data migration. 16 of the 17 volumes initialized just fine, but I was getting an error on the one volume that had a LUN inside. It was a SnapDrive for Windows LUN, so I knew that just prior to the final cutover I’d have to take a Snapshot via SnapDrive, but I should be able to start the baseline transfer via the standard CLI. Here’s what I was seeing:
ControllerA> snapmirror initialize -S ControllerZ-vif01:vol_server2008 ControllerA:vol_server2008 Transfer started. Monitor progress with 'snapmirror status' or the snapmirror log. Mon May 13 14:21:26 CDT [ControllerA:replication.dst.err:error]: SnapMirror: destination transfer from ControllerZ-vif01:vol_server2008 to vol_server2008 : process was aborted.
I was asked by a client yesterday in passing how to check CPU utilization on one of their NetApp filers. I didn’t immediately know where to go and we quickly moved on to something else. So as I was showering this morning, as I do many mornings, I remembered that, of course, you can use sysstat to view performance data. Anyways, this is a real nice way to view instantaneous general performance data. Options for this command are shown below.
deathstar> sysstat ?
usage: sysstat [-c count] [-s] [-u | -x | -m | -f | -i | -b] [interval]
-c count – the number of iterations to execute
-s – print out summary statistics when done
-u – print out utilization format instead
-x – print out all fields (overrides -u)
-m – print out multiprocessor statistics
-f – print out FCP target statistics
-i – print out iSCSI target statistics
-b – print out SAN statistics
interval – the interval between iterations in seconds, default is 15 seconds
I had the opportunity to configure SnapMirror for a client today and it gave me a bit of a headache. I did what I thought was my due diligence: reading the relevant vendor documentation for SnapMirorr for each version of Data ONTAP, 7.3.2 and 8.0.3P3. What I failed to do was read a few lines further than I actually did – I missed a simple piece of syntax that turned a 30 minute WebEx into a 2 hour ordeal. I learned a good lesson about SnapMirror during this engagement, though, and I’d like to share it.
The SnapMirror of these three volumes were actually for a data migration because the source filer is being decommissioned. The general steps required in the engagement today were as follows:
<> Run a cable between what will be the dedicated replication links on each filer
<> Configure each interface with IP settings
<> Ensure SnapMirror is licensed and enabled on each filer
<> Configure /etc/hosts and /etc/snapmirror.allow files on source filer
<> Configure /etc/hosts and /etc/snapmirror.conf files on destination filer
<> Initialize the baseline replicaction
Edit: To jump to the good stuff, check out Neil Anderson’s free eBook, How to Build a NetApp ONTAP 9 Lab for Free!
I’d like to share quick note about my experience in studying for and taking the NetApp Certified Data Management Administrator exam for Data ONTAP 8.0 7-Mode, NS0-154. Perhaps someone out there will find the links and study methods here useful .
I’ve never held a pure Storage Administrator position, but I did recently complete a year-long contract implementing NetApp FAS3240 and FAS3270 filers as part of an Enterprise Virtualization Project for the US Army in Southwest Asia. I was actually hired as a Network Engineer to install, configure and migrate to Cisco Nexus 5020s and 2224 Fabric Extenders, but coming from a Systems background, I was able to perform the role of Implementation Engineer for the VMware, NetApp, and Nexus environments. It was a very satisfying role overall and one in which I gained a lot of varied experience.
Where am I? It’s dark and I’ve lost my network settings! How innocuous editing of NetApp config file can lead to lost IPsPosted: February 24, 2012
So I was performing an initial configuration of a FAS3270 the other day when I changed the interface group information via PuTTY. Specifically, I deleted and recreated the interface groups manually instead of running setup. After I did this and following a reboot of the filer, the IP addresses for both interface groups were missing. Performing an ‘ifconfig -a’ before the reboot, I saw the IP addresses assigned correctly:
In speaking to my fellow Implementation Engineers and team leads, I’ve come to learn file system misalignment is a known issue in virtual environments and can cause performance issues for virtual machines. A little research has provided an overview of the storage layers in a virtualized environment, details on the proper alignment of guest file systems, and a description of the performance impact misalignment can have on the virtual infrastructure. NetApp has produced a white paper that speaks to file system alignment in virtual environments: TR 3747, which I’ve reproduced below.
In any server virtualization environment using shared storage, there are different layers of storage involved for the VMs to access storage. There are different ways shared storage can be presented for the hypervisor and also the different layers of storage involved.
VMware vSphere 4 has four ways of using shared storage for deploying virtual machines: