Skip to main content

Posts

How to reclaim unused space for SQL DB

Error: Many times, after deleting SQL data from tables won't reclaim the unused space. Solution: Easy way is to click DB from SQL Studio Tasks->Shrink ->Files Choose the default "release unused space" option.

How to use vdbench for create random data files

 Vdbench is a controlled I/O load simulation tool for storage systems developed by oracle as an open source.  It works with Linux and Windows  Written in Java and C Vdbench has three basic definitions in the configuration file. SD or storage definition: This defines what storage to use for the testing. WD or workload definition: This defines the workload parameter for the testing. RD or run definition: This defines storage, workload and run duration. Storage definition SD defines the storage used for the testing. Make sure you select the right storage or else everything on the selected disk could get destroyed. The SD name should be unique. sd=default,size=100g sd=sd1,lun=/dev/sdb0 sd=sd2,lun=/dev/sdb1,size=100g sd=sd3,lun=/dev/sdb2,size=200g Workload definition WD defines the workload used by the script for testing. The WD name must be unique. WD parameters include the following: sd – Test device seekpct – Percentage time to move location rdpct – Read percentage xfersize...

ESXi gets disconnected from vCenter server intermittantly

 Issue: ESXi gets disconnected from vCenter server intermittantly Solution: This issue occurs when the UDP heartbeat message sent by ESX/ESXi host is not received by vCenter Server. Select the  vCenter  object from the inventory under  Hosts and Clusters . Select the  Manage  or  Configure  tab. Select  Settings  >  Advanced Settings . Click  Edit . and add new value In the  Key  field, type: config.vpxd.heartbeat.notRespondingTimeout   In the  Value  field, type: 120   Click  Add . Click  OK .      9.SSH to vCenter with root credentails and restart below service:  [ ~ ]# service-control --stop vmware-vpxd; service-control --start vmware-vpxd Operation not cancellable. Please wait for it to finish... Performing stop operation on service vpxd... Successfully stopped service vpxd Operation not cancellable. Please wait for it to finish... Performing start operation on ...

resized volume size not detecting VMware existing datastore

 Issue: resized backend volume size from storage array. but the VMware ESXi datastore size not getting increased after "refresh capacity" also. Tried storage iscsi adapter rescan/refresh as well, Solution:   Go to Existing datastore ->Configure find out the Lun ID of the existing datastore (can be found from Storage array where you provided LUN id)  right click on the Datastore and choose "Increase capacity" option, in the next wind select the existing LUN ID and complete the steps. Now you will see the new Datastore size.

iperf3 to measure network bandwidth between linux servers

 1.Install iperf3 on both server and client:     download:  https://iperf.fr/iperf-download.php#fedora     Install with: rpm -ivh iperf3-3.1.3-1.fc24.x86_64.rpm 2.Run server to listen on port 5201 with below command:    iperf3 -s -f K Example:  /]# iperf3 -s -f K ----------------------------------------------------------- Server listening on 5201 ----------------------------------------------------------- Accepted connection from 10.10.10.1, port 44246 [  5] local 10.10.1.1 port 5201 connected to 10.10.10.1 port 44248 [ ID] Interval           Transfer     Bandwidth [  5]   0.00-1.00   sec  3.01 GBytes  3157621 KBytes/sec [  5]   1.00-2.00   sec  4.20 GBytes  4399773 KBytes/sec [  5]   2.00-3.00   sec  2.20 GBytes  2305199 KBytes/sec [  5]   3.00-4.00   sec...