Using SSD drives is no longer an exception, they are used in home systems but also in server systems to hold at least the OS, or other resources that need more speed than space. As any other storage disk a SSD can become fragmented as successive write/delete operations will try to use the available storage.… Read More »
This is a follow-up tutorial on the DRBD replication posts about resynchronization of sites after the failed DR site is recovered. More than a year ago I described in a long tutorial how to use DRBD in a real production environment and the challenges associated to it. See: DRBD based disk replication of a production… Read More »
This is a follow-up tutorial on the DRBD replication posts about resynchronization of sites after the failed PR site is recovered (DRBD split brain recovery). More than a year ago I described in a long tutorial how to use DRBD in a real production environment and the challenges associated to it. See: DRBD based disk… Read More »
This is a follow up tutorial on the DRBD replication posts about promoting the DR site as the main site when PR is failed. More than a year ago I described in a long tutorial how to use DRBD in a real production environment and the challenges associated to it. See: DRBD based disk replication… Read More »
This is a follow up tutorial on the DRBD replication posts about gracious role switching of live sites configured with DRBD replication. More than a year ago I described in a long tutorial how to use DRBD in a real production environment and the challenges associated to it. See: DRBD based disk replication of a… Read More »
I had a situation when from a strange reason a default grub setup as a result of a system recovery was missing the lvm and raid modules so I was not able to boot. I have the following setup on the server: – my boot partition is in fact an ext4 partition over a mdraid… Read More »
There are times when even experimented sysadmins do stupid things. One of that moments happened to me when I tried some speed tests on my ssd RAID1. The result was not so satisfactory. Corrupted /boot partition with missing files and orphan inodes. To make things more complicated I have the following constraints that make this… Read More »
My desktop Dell XPS 8700 is a beast even after more than 2 years of the official release. The problem with it is that in a typical big corporate fashion it contains an unbalanced set of hardware: * A very fast processor * 16GB of memory (4x4GB so not so up-gradable to the 32GB maximum)… Read More »
1 General Considerations Our example enterprise applications run on a Linux Cluster with a shared cluster storage resource. Having this HA setup ensures that we have a high rate of service availability on the production site. To ensure that the disruption time in service of our enterprise application is minimal as possible the best solution… Read More »
The following configuration was created to use the iSCSI exported resources from a NetApp storage device as shared disk resources in a Linux cluster environment. The same resources are also replicated to a remote cluster using DRBD disk replication. The production environment contains four exported SAN resources which will be used as shared resources in… Read More »