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The value of an all-in-one storage stack

storageJul 29, 2007 1 min read

I have written several times about the Solaris Leadvilel storage stack. While debugging a problem on a Solaris 9 host that wasn't using the Leadville stack, I would wait and wait and wait for various commands to complete. Here is one such example: real 2:25.09 user 0.10 sys 0.45 After migrating the same host to Solaris 10 and the Leadville stack, I no longer had to wait for my commands to complete. Here is an example: real 0.11 user 0.05 sys 0.03 After doing a bit of debugging, I noticed that the Solaris 9 fibre channel stack (which was using a vendor supplied HBA driver) was enumerating each path to see if devices were present…

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Viewing tape devices on Solaris hosts

storageJul 29, 2007 1 min

I have been repairing our backup environment for the past few weeks, and have encountered several nifty tools in the Netbackup volumen management bin directory. Once of these tools is the scan utility, which displays the robots and tape devices visible to a system: This utility is extremely useful for getting the device paths for a specific tape device, and for viewing the information returned from a SCSI INQUIRY command. Viva la scan!

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Configuring Brocade switches to log to syslog

storageJul 15, 2007 1 min

I manage a number of Brocade switches, and periodically they encounter hardware problems (bad SPFs, faulty cables, etc.). To ensure that I am notified when these problems occur, I like to configure the switches to log errors to a centralized syslog server. Configuring a Brocade switch to use syslog is as simple as running the syslogdIpAdd command with the IP address of the syslog server: switch1:admin> syslogdIpAdd "192.168.23.138" Committing configuration...done. switch1:admin> syslogdIpAdd "192.168.23.139" Committing configuration...done…

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Viewing port utilization on Brocade switches

storageJul 15, 2007 1 min

The Brocade Silkworm family of switches maintain a number of important performance and reliability counters for each switch port. Performance and reliability counters for specific switch ports can be viewed with the porterrshow, portshow and portStatsShow commands. To view system wide throughput statistics, the portPerfShow command can be run with an optional interval: The individual switch ports are listed above the dashes, and the numbers below the dashes contain the number of bytes transmitted and received per second. This is a super useful tool for getting a high level overview of what your switch is doing.

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Backing up Brocade switch configurations

storageJul 7, 2007 1 min

Brocade switches have become one of the most widely deployed componets in most Storage Area Networks (SANs). One thing that has led to Brocade's success is their robust CLI, which allow you to view and modify almost every aspect of their switch. This includes zoning configurations, SNMP attributes, domain ids, switch names and network addresses, etc. All of this configuration information is necessary for the switch to function properly, and should be periodically backed up to allow speedy recovery when disaster hits…

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