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Portal:Data Services/Admin/Wiki Replicas
This page is currently a draft.
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This page holds all the knowledge we have regarding Wiki Replicas for admins.
Service architecture by layers
Description of how the service is currently deployed.
Here is a general diagram of how things are:
This service is build on top of several physical servers:
All servers are the same:
- HP ProLiant DL380 Gen9
- 16 CPU Intel(R) Xeon(R) CPU E5-2637 v3 @ 3.50GHz
- 500GB RAM
- 1 hard-disc in /dev/sda with 11.7 TiB (probaby RAID, using hpsa kernel driver)
- 4 x 1GB ethernet interfaces (tg3)
- isn't this information somewhere else?
- no RAID status monitoring from userspace?
The service has a concrete storage configuration.
As seen by fdisk:
% sudo fdisk -l Disk /dev/sda: 11.7 TiB, 12802299617280 bytes, 25004491440 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 262144 bytes / 2097152 bytes Disklabel type: gpt Disk identifier: 0933E022-348E-4F59-8F84-D4C3B32090BD Device Start End Sectors Size Type /dev/sda1 4096 78123007 78118912 37.3G Linux filesystem /dev/sda2 78123008 93749247 15626240 7.5G Linux swap /dev/sda3 93749248 25004490751 24910741504 11.6T Linux LVM Disk /dev/mapper/tank-data: 11.6 TiB, 12754295455744 bytes, 24910733312 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 262144 bytes / 2097152 bytes
As seen by the LVM stack:
% sudo pvs PV VG Fmt Attr PSize PFree /dev/sda3 tank lvm2 a-- 11.60t 0 % sudo vgs VG #PV #LV #SN Attr VSize VFree tank 1 1 0 wz--n- 11.60t 0 % sudo lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert data tank -wi-ao---- 11.60t
As seen by df:
% df -h Filesystem Size Used Avail Use% Mounted on udev 252G 0 252G 0% /dev tmpfs 51G 4.1G 47G 8% /run /dev/sda1 37G 11G 25G 31% / tmpfs 252G 0 252G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 252G 0 252G 0% /sys/fs/cgroup /dev/mapper/tank-data 12T 6.5T 5.2T 56% /srv
All 3 servers should have more or less the same storage configuration.
The databases in this service have a concrete layout/configuration.
Such as applications running on top, proxys, caches, et al.
From production to wiki-replicas
Wiki databases from production are copied and sanitized to serve wiki-replicas.
Docs to perform common tasks related to this service. As detailed as possible.
Before this new cluster, we had an old cluster composed of physical servers: labsdb1001, labsdb1002 and labsdb1003. At the time of this writing, the last standing server is labsdb1003, which is going down in December 2017.