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Convert Zone Info to Nicknames for VirtualWisdom

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VirtualWisdom uses “Nicknames” or “Aliases” to give human-readable names to attached SAN devices, reducing the time to locate a problem device, but also to help group devices logically as being the same server or storage, and into business units for SLAs and escalation of issues.

We know that Nickname management can be a hassle, but the obvious gains make it worthwhile, so some of our work in Services is helping customers draw this data from existing repositories such as fabric Zoning information. Maintaining aliases in your zones, then converting those to nicknames, means that you only need to maintain one repository of names.

This “How-to” article is targeted at showing how to do this in common environments. As a VI Application Engineer, my content on this feed tends to be more of a lower-level “how to” in nature. This content has been in our internal self-help content, but may be difficult to find.

Collection, then Conversion

Diagram of data-flow of nicknames from switches to VirtualWisdom

The general process tends to be collecting the data, then converting to a compatible format for import. Let’s focus first on Collection, which tends to be a script running at scheduled times during the day or week.

Scripting under Schedule

This tends to be done as a batch file that is triggered through a scheduler such as the Windows Scheduler running a BAT file, or a UNIX-like OS running a shell script from cron or as a passive check under tools such as Icinga.

Where fabric-wide data is used, only one switch per fabric needs be queried. I tend to use the least-busy switch to avoid adding any load to Core switches or other busy switches.

Will DBTools Work for You?
The easiest method if you have small switches is to use Program FilesVirtual InstrumentsVirtualWisdomUnSupportedDBToolsDBTools.exe tool, but running it as a batch command. This tool will connect to the switch using SSH, query the information, and convert it to the right format for import. In essence, the collection and conversion is a single step. For example, using the example username “scott”, password “tiger”, switch IP 192.168.0.1, to a file FabricA.csv in the import directory:

Brocade “alishow”: (the command is all on one line)
DBToolScript.bat -n -st brocade -u scott -p tiger -ip 192.168.0.1 D:VirtualWisdomDataDeviceNicknameFabricA.csv

Cisco “fcalias”:
DBToolScript.bat -n -st cisco -u scott -p tiger -ip 192.168.0.1 D:VirtualWisdomDataDeviceNicknameFabricA.csv

For example:

screen cap of the DBToolScript -n run
(In this example, my demo server has the database on the C: drive; this is not the recommended config for production servers! Also, notice how the DBToolScript cannot open a log file — running this command in your VirtualWisdomData directory will allow it to write a log to .LogDBToolLog )

Putting commands such as this into a batch file running daily via Windows Scheduler, and configuring a scheduled Import via the VirtualWisdom Scheduler, your job is complete!

The DBTools command doesn’t understand all possible nickname sources, and may have problems on some switches; if this method doesn’t work for you, then we resort to the two-stage process. This less-polished method is a bit more versatile, but isn’t as pretty. Once configured, though, it tends to work reliably.

Collection

The more manual collection can be done from four different sources:

  1. Brocade Switch using “zoneshow”
  2. Brocade Switch using “alishow”
  3. Cisco Switch using “show device-alias database”
  4. Cisco Switch using “show fcalias”

Collection requires non-interactive SSH tools such as plink.exe available from the makers of Putty; google should help you find it, but if you cannot, VI can help redirect you. The general command is:

plink.exe -l username -pw password IP.IP.IP.IP "command" > intermediate.file

For example: (using scott, tiger, 192.168.0.1, and a Brocade/zoneshow switch)

plink.exe -l scott -pw tiger 192.168.0.1 zoneshow > sw-192.168.0.1.zone

… and a Cisco/”show device-alias database” at 192.168.0.3:

plink.exe -l scott -pw tiger 192.168.0.3 "show device-alias database" > sw-192.168.0.3.cisco

These commands give no output when they run, except the first time: the plink.exe command wants you to accept a key to later ensure you are not vulnerable to a man-in-the-middle attack, which looks like the following: (accept the key once, later you won’t be asked unless it changes)

Again, you only need to collect zoning information or fabric-wide alias information from one switch per zone. With a unique filename per fabric, you’re ready to convert these files.

Conversion

Brocade and Cisco tend to use consistent formats for their outputs, but they are in text format. Most times, the two scripts work for this. These are scripts for the “awk” tool, which can be extracted from the UnxUtils project, or using Microsoft’s tools for UNIX. Either method gives you a “awk.exe” or a “gawk.exe”, which will execute these scripts:

  1. brocade-alishow2wwncsv.awk
  2. cisco-devicealias2wwncsv.awk

Conversion of a Brocade zonecfg or alishow is done as:

gawk.exe -f brocade-alishow2wwncsv.awk sw-192.168.0.1.zone > D:VirtualWisdomDataDeviceNicknameFabricA.csv

Whereas conversion of a Cisco device-alias database or fcalias is done as:

gawk.exe -f cisco-devicealias2wwncsv.awk sw-192.168.0.3.cisco > D:VirtualWisdomDataDeviceNicknameFabricB.csv

Note: these runs are redirecting output to files, so these commands give no visible output to the cmd.exe screen except in the case of errors.

Complete Example

A complete example of collection and conversion may look like the following code. Be aware, we tend to recommend using full pathnames (i.e. C:Program Filessomethingelseplink.exe) to ensure the commands are found regardless %PATH% variable and working directory. This example is simplified to be more readable but does run as-is given the right environment and working directory.

@echo off

plink.exe -l scott -pw tiger 192.168.0.1 "show device-alias database" > sw-192.168.0.1.cisco
plink.exe -l scott -pw tiger 192.168.0.2 "show fcalias" > sw-192.168.0.2.cisco
plink.exe -l scott -pw tiger 192.168.0.3 "zoneshow" > sw-192.168.0.3.zone
plink.exe -l scott -pw tiger 192.168.0.4 "alishow" > sw-192.168.0.4.zone

gawk.exe -f brocade-alishow2wwncsv.awk sw-192.168.0.3.zone sw-192.168.0.4.zone > nicknames.csv
gawk.exe -f cisco-devicealias2wwncsv.awk sw-192.168.0.1.cisco sw-192.168.0.2.cisco >> nicknames.csv

This example generates a single file; the configuration to import this one file is as follows (briefly shown here because the User Guide has more detail regarding Schedules):

  1. Views Application, Setup tab: Views Application, Setup Tab
  2. “Schedules” page, roughly 5th item down: Views Application, Setup Tab, Schedules page
  3. Create a new Schedule, with the action “Import WWN Nicknames”: Views Application, Setup Tab, Nickname Import Schedule
  4. …and configure it to use a new WWN Importing Configuration, as follows. NOTE we only use a local filename, all files are in the DeviceNickname directory of your VirtualWisdomData folder:Nickname Import configuration, nicknames.csv

Controlling Over-Provisioning of Your Storage Ports

Best Practices, latency, over-provisioning, SAN, storage arrays, VirtualWisdom No Comments »

While it’s generally accepted that SAN storage utilization is low, only a few industry luminaries, such as John Toigo, have talked about the severe underutilization of Fibre Channel (FC) SAN fabrics.  The challenge, of course, is that few IT shops have actually instrumented their SANs to enable accurate measurements of fabric utilization.  Instead, 100% of enterprise applications get the bandwidth that perhaps only 5% of the applications, wasting CAPEX need. 

In dealing with several dozen large organizations, we have found that nearly all FC storage networks are seriously over-provisioned, with average utilization rates well below 10%.  Here’s a VirtualWisdom dashboard widget (below) that shows the most heavily utilized storage ports on two storage arrays, taken from an F500 customer.  The figures refer to “% utilization.”

Beyond the obvious unnecessary expense, the reality is that with such low utilization rates, simply building in more SAN hardware to address performance and availability challenges does nothing more than add complexity and increase risk.  With VirtualWisdom, you can consolidate your ports, or avoid buying new ones, and track the net effect on your application latency to the millisecond.  The dashboard widgets below show the “before” and “after” latency figures that resulted from the configuration changes to this SAN, using VirtualWisdom.  They demonstrate a negligible effect.

Latency “before”

Latency “after”

Our most successful customers have tripled utilization and have been able to reduce future storage port purchases by 50% or more, saving $100 – $300K per new storage array.

For a more detailed discussion of SAN over-provisioning, click here, or check out this ten-minute video discussing this issue and over-tiering.

Eager Attendees Ready to Learn During Hands-On-Lab Sessions at Spring SNW 2012

Best Practices, Hands-On Lab, SAN, SNW, storage, VirtualWisdom No Comments »

 At the spring Storage Network World (SNW) show in Dallas, I had the pleasure of teaching the hands-on lab session for VirtualWisdom with Andrew Benrey, VI Solutions Consultant, and we had a fantastic response to our “Storage Implications for Server Virtualization” session. We co-presented with Avere and HP 3par, and during the two-hour session, we covered how to use VirtualWisdom to administer and optimize a fiber channel SAN, NAS optimization with the Avere appliance and the use of thin provisioning and reclamation using the HP 3par arrays.

The lab exercises covered all areas of SAN administration. The first exercise looked at how we discover and report physical layer errors. We then looked at queue depth performance, imbalanced paths, and detection of slow-draining devices using buffer-to-buffer credits. In the last exercise, we reviewed a VMware infrastructure showing the virtual machines, fiber channel fabric and SCSI performance.

I found it interesting that for most of the lab sessions, many students picked the VirtualWisdom lab to start with. I believe that with the demand for proactive SAN management, more and more people are finding out about the benefits of VirtualWisdom, and came to the hands-on-lab to see for themselves. When looking at the attendance numbers, our lab was sold out for most sessions. Our most popular session had a sign up list of 52 for 20 seats.  During the six sessions we conducted, we were able to meet and talk with almost 500 attendees in depth about the need for tools like VirtualWisdom and the advantages this platform offers for SAN teams working in a virtualized environment.  Attendees liked the ability to quickly walk through the infrastructure from the ESXi server down to the storage array and spot the anomalies. The ability to go back in time was also of importance. Several customers were in the lab as part of their product evaluation.

Those of you who have seen VirtualWisdom understand how rich our user interface can be. For the lab exercises, I specifically divided up exercises so that the lab attendees had a much simpler and more easily understood interface in which to work. This turned out well as very few of the attendees needed additional help in working with the Dashboard interface.

Storage Network World Hands-On Lab Infrastructure

Issues with VMs' Lost Performance

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In tuning a product that is a write-intensive database tool, we’ve found that performance on a VM can be wildly inconsistent. The hardest thing to explain is why we see a 30% performance drop and slow commits when moving from physical servers to the same-size physical server holding one VM generated form that server: literally the same system, but with a VM layer.

Shoot, 37 Signals had this performance impact:

Of course, layering in a VM lets us VMotion the process, if we weren’t using a lot of local disk (since the local disk doesn’t move with it). NAS? Bwa ha ha ha, please no, corporations with I/O response requirements use SAN. Sure, SAN is expensive, but it shares the disk nicely unless you need to use the tool to monitor the SAN — SAN congestion slows the tool you need to fix it 🙂

Layering a VM tends to be satisfying a corporate requirement of “everything on VM”.

When considering Tuning the MySQL InnoDB Engine, keep in mind that if it’s on a VM, you can’t guarantee accuracy of the numbers you’re using to tune.

De-risking SAP Performance and Availability

Best Practices, SAP, VirtualWisdom No Comments »

It’s no secret that many enterprise mission critical IT implementations depend on SAP.  In 2008, the Standish Group estimated the average cost of an ERP downtime at $888K per hour. If you’re an SAP user, you probably have some idea of your cost of downtime.

What’s surprising to me is that often companies still rely on massive over-provisioning to handle the database growth and ensure that their infrastructure can meet the level of performance and availability required for informal or formal Service Level Agreements.  On one level, it’s understandable, because the stakes are so high.  But we’re starting to see a trend towards better instrumentation and monitoring, because, while the stakes are high, so are the costs.

The truth is, the performance of SAP is usually not bottlenecked by server-side issues, but rather by I/O issues.  Unfortunately, most of today’s monitoring solutions, including the best known APM solutions, have a tough time correlating your applications with your infrastructure.  The “link” between the application and the infrastructure is often inferred, or is so high level that deriving actual cause and effect is still a guessing game.

Many of our largest customers de-risk their SAP applications using VirtualWisdom to directly correlate the infrastructure latency to their application instances.  In this simple dashboard widget (below), an application owner tracks, in real time, the application latency, in milliseconds, caused by the SAN infrastructure.

With this level of tracking and correlation, many of the largest SAP and VirtualWisdom customers have successfully de-risked their growing, mission-critical SAP deployments.

To hear our Director of Solutions Consulting Alex D’Anna discuss this issue in more detail, I encourage you to attend his 35-minute On-Demand webcast.

Spring 2012: Storage Networking World

Best Practices, Dallas, SNW, storage, virtualization, VirtualWisdom No Comments »

It was great to be at the Storage Networking World (SNW) show in Dallas last week. We saw more customers sending people from the operations and the architecture/planning groups. It’s important for operations and architecture/planning to work together on SAN infrastructure, so it was good to see this and to hear some of the attendee’s remark they were hired to bridge the gap between these groups.

In a panel of CIOs at medium to large companies, all agreed that staffing remains a huge issue.  No one is getting new headcount, yet the number of new technologies they have to work with continues to grow.  Some saw a solution in cross-training IT staff.  One CIO is creating “pods” where architects and planners work closely with operations.  Everyone agreed that even though the effect of training and cross-training staff often results in “poaching,” it was still worth it to have a better-trained staff.  At Virtual Instruments, we agree with this trend and see cross-domain expertise taking on a more of an important role. VirtualWisdom, for instance, is designed for use by everyone in the infrastructure, from the DBAs and server admins to the fabric and storage admins.

Stew Carless, Virtual Instruments Solutions Architect, held a well-attended session on, “Exploiting Storage Performance Metrics to Optimize Storage Management Processes.”  In the session, Stew talked about how using the right instrumentation can go a long way towards eliminating a lot of the guessing game that often accompanies provisioning decisions.

Over at the Hands-on-Lab, Andrew Benrey and I led the Virtual Instruments part of the “Storage Implications for Server Virtualization” session. We had a full house for most of the sessions and we were pleased that many of the lab attendees were familiar with Virtual Instruments before they participated in the lab.

In a real-time illustration of managing the unexpected: The big news at the show came from the U.S. weather service, when a series of tornados ripped through the Dallas area to the east and west of the hotel. The SNW staff and the hotel did an excellent job of gathering everyone on the expo floor and sharing updates on what was happening. After a two-hour interruption, the SNW staff did a great job of getting the conference back underway. The expo exhibitors enjoyed the two hours of a captive audience!

With a couple of exceptions, many of the big vendors weren’t at SNW, which we see as a positive trend.  People come to these events to learn about new things, and frankly, the newest things come from the newest, smallest vendors.  At SNW, the floor was full of smaller, newer vendors who may not have direct sales forces who can blanket continents, but whose fresh insights and new approaches provided valuable insights for the SAN community.  I didn’t hear one end user complain that their favorite big vendor wasn’t there.

The next Storage Network World show will be in Santa Clara this October. We are looking forward to meeting everyone again and to catch up on what’s going on.

 

 

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