Skip to content

sql-server-linux-replication-snapshot-shares.md

Latest commit

 

History

History
142 lines (99 loc) · 4.46 KB

sql-server-linux-replication-snapshot-shares.md

File metadata and controls

142 lines (99 loc) · 4.46 KB
title Configure snapshot folder shares
titleSuffix SQL Server on Linux
description Learn to configure snapshot folder shares SQL Server replication on Linux.
ms.custom seo-lt-2019
author VanMSFT
ms.author vanto
ms.reviewer vanto
ms.date 09/24/2018
ms.topic article
ms.prod sql
ms.technology linux
monikerRange >=sql-server-ver15||>=sql-server-linux-ver15

Configure replication snapshot folder with shares

[!INCLUDE SQL Server - Linux]

The snapshot folder is a directory that you have designated as a share; agents that read from and write to this folder must have enough permissions to access it.

replication diagram

Replication Snapshot Folder Share Explained

Before the examples, let's walk through how SQL Server uses samba shares in replication. Below is a basic example of how this works.

  1. Samba shares are configured that files written to /local/path1 by the replication agents on publisher can be seen by the subscriber
  2. SQL Server is configured to use share paths when setting up the publisher on the distribution server such that all instances would look at the //share/path
  3. SQL Server finds the local path from the //share/path to know where to look for the files
  4. SQL Server reads/writes to local paths backed by a samba share

Configure a samba share for the snapshot folder

Replication agents will need a shared directory between replication hosts to access snapshot folders on other machines. For example, in transactional pull replication, the distribution agent resides on the subscriber, which requires access to the distributor to get articles. In this section, we'll go through an example of how to configure a samba share on two replication hosts.

Steps

As an example, we will configure a snapshot folder on Host 1 (the distributor) to be shared with Host 2 (the subscriber) using Samba.

Install and start Samba on both machines

On Ubuntu:

sudo apt-get -y install samba
sudo service smbd restart

On RHEL:

sudo yum install samba
sudo service smb start
sudo service smb status

On Host 1 (Distributor) Set-up the Samba share

  1. Set-up user and password for samba:
sudo smbpasswd -a mssql
  1. Edit the /etc/samba/smb.conf to include the following entry and fill in the share_name and path fields
 <[share_name]>
 path = </local/path/on/host/1>
 writable = yes
 create mask = 770
 directory mask 
 valid users = mssql

Example

[mssql_data]    <- Name of the shared directory
path = /var/opt/mssql/repldata <- location of directory we wish to share
writable = yes  <- determines if the share is writable from other hosts
create mask = 770  <- Linux permissions for files created 
directory mask = 770 <- Linux permissions for directories created
valid users = mssql   <- list of users who can login to this share

On Host 2 (Subscriber) Mount the Samba Share

Edit the command with the correct paths and run the following command on machine2:

sudo mount //<name_of_host_1>/<share_name> </local/path/on/host/2> -o user=mssql,uid=mssql,gid=mssql

Example

mount //host1/mssql_data /var/opt/mssql/repldata_shared -o user=mssql,uid=mssql,gid=mssql

user=mssql <- sets the login name for samba
uid=mssql   <- makes the mssql user as the owner of the mounted directory
gid=mssql   <- sets the mssql group as the owner of the mounted directory

On Both Hosts Configure SQL Server on Linux Instances to use Snapshot Share

Add the following section to mssql.conf on both machines. Use wherever the samba share for the //share/path. In this example, it would be //host1/mssql_data

[uncmapping]
//share/path = /local/path/on/hosts/

Example

On host1:

[uncmapping]
//host1/mssql_data = /local/path/on/hosts/1

On host2:

[uncmapping]
//host1/mssql_data = /local/path/on/hosts/2

Configuring Publisher with Shared paths

  • When setting up replication, use the shares path (example //host1/mssql_data
  • Map //host1/mssql_data to a local directory and the mapping added to mssql.conf.

Next steps

Concepts: SQL Server replication on Linux

Replication stored procedures.