Deployment Options
Frank [email protected]
]project-opem[ 2007, Title / Speaker / 2
SaaS Hosting What is SaaS Hosting? SaaS Hosting Pros & Cons
Hosting @ Home Hosting @Home Pros & Cons A Typical Hosting @ Home Configuration How Everything Works Together Backup & Data Security Best Practices Sizing Simplified Network Architecture Software Configuration
Contents
]project-opem[ 2007, Title / Speaker / 3
SaaS Hosting(Software as a Service)
A cost efficient option for small and medium companies.No need for IT sophistication.
]project-opem[ 2007, Title / Speaker / 4
What is SaaS Hosting?
Software as a Service ]po[ sets up your server together with several
other servers in the ]po[ hosting center ]po[ takes care of backup, security and other
system administration tasks The service is billed monthly
Flexible Options Several hosting options are available with
different performance levels ]po[ provides you with the option to switch to
any of the other hosting models
]project-opem[ 2007, Title / Speaker / 5
SaaS Hosting Pros & Cons
Advantages No specific IT skills necessary in your company Little up-front investment required Professionally managed backup and security Service is available even if your internet connectivity is
down Highest availability for external users
Disadvantages File transfer speed is lower then on the local fileserver Internet failures can disrupt your business
]project-opem[ 2007, Title / Speaker / 6
Hosting @Home
A cost efficient option for companies of all sizes with a certain degree of technology sophistication.Maintenance is handled remotely by a ]po[ administrator.
]project-opem[ 2007, Title / Speaker / 7
Hosting @Home Pros & Cons
Advantages Fastest network connection Seamless integration with the local file server Sophisticated backup options available Easy physical access to the servers Service is available in the office even if the
Internet connection is down Highest availability for users in the same office
Disadvantages Some IT sophistication in-house is necessary Higher total cost then SaaS hosting
]project-opem[ 2007, Title / Speaker / 8
Security Features1. An aDSL router provides a cheap
connection to the Internet2. A backup connection provides
connectivity in case of a aDSL failure3. A firewall provides controlled access from the Internet4. A RAID array allow the productive server to survive
the crash of a single hard disk5. A tape device allows for daily backups of all corporate
data.6. A backup server is ready to take over in case of a
failure of the main server.7. Uninterruptible power Supplies
(UPS) protect the system from power failures.
A Typical Hosting @ Home Configuration
UPS UPS UPS
Internet
BackupServer
Server
Firewall
aDSL aDSL
Hub/Switch
Tape
PC PC PC PC PC
Freelance A
Freelance B
RAIDRAIDRAIDRAID
RAIDRAIDRAIDRAID
LAN
SecondaryPrim
ary
3
4
6
5
1 2
7
]project-opem[ 2007, Title / Speaker / 9
Linux ]po[ Production Server
Windows File Server
1. AOLServer is ]po[‘s “Application Server”…
2. …and executes the ]po[ code3. All data are stored in a PostgreSQL
database4. The data are copied daily to the backup
server5. The backup server contains an exact
copy of the production server, ready to take over in the case of a failure.
6. Documents and files are stored in a normal Windows file server with local backup.
7. The ]po[ servers “mounts” the Windows file server share in order to access the files. The files stay on the Windows server.
How Everything Works Together
AOLServer
FileServer
Linux ]po[ Backup Server
PostgreSQL
]po[ Code
AOLServer
PostgreSQL
]po[ Code
Ba
cku
p
1
2
3
4
5
6
7
7
]project-opem[ 2007, Title / Speaker / 10
Backup Policies All server should be equipped with
RAID arrays. We recommend a weekly full-backup
of all data on a tape or similar device in order to be able to keep multiple versions.
The backup server should receive daily database backups of the production server in order to speed up the recovery process.
BackupServer
ServerTapeRAIDRAIDRAIDRAID
RAIDRAIDRAIDRAID
1
2
Backup Scheme1. Data are stored on
a RAID array2. Daily tape backup3. Daily backup to
backup server for quick recovery
3
Backup & Data Security Best Practices
]project-opem[ 2007, Title / Speaker / 11
We recommend two identical servers as “production” and “backup + test” servers
“Active users” are those users who are requesting 1-10 ]po[ pages per minute
We recommend PostgreSQL for all but the largest installations
BackupServer
ServerTapeRAID
RAIDRAIDRAID
RAIDRAIDRAIDRAID
Active Users Computer Memory Hard Disk
1-5 Normal desktop computer, even VMware
>1 GByte IDE RAID
5-10 Small Linux server with 1 dual-core processor
>2 Gbyte SCSI RAID
10-20 Linux server with 2 processors with 2-4 cores each.
>4 GByte SCSI RAID
20-50 Linux server with 4 processors with 2-4 cores each.
>8 GByte SCSI RAID
>50 Linux server with >8 processors and Oracle database
>16 GByte SCSI RAID plus storage network
Sizing
]project-opem[ 2007, Title / Speaker / 12
For small companies (<10 active users, <30 employees)
Two ordinary PCs serve as servers. 2 SATA disks per computer act as RAID
A tape backup is attached to the productive server for daily backups.
A single aDSL lines provides Internet access
The aDSL router acts as a mini-firewall (packet filter)
Internet
Freelance A
Freelance B
Telephone
UPS UPS
aDSL
Hub/Switch
PC PC PC PC PC
LAN
Connection
PC PCTape
Simplified Network Architecture
]project-opem[ 2007, Title / Speaker / 13
Configuration We recommend Linux for the production and backup
server (preferably RHEL or CentOS, alternatively Open SuSE 10.x, no SuSE Enterprise Server!)
PostgreSQL 8.2 for < 50 active users Backup and failover configuration for operating system,
database and user data File storage kept apart from the ]po[ server. System Monitoring (BigBrother, Nagios, …)
Documentation Please see the “Operations & Maintenance Guide” for
operation procedures
Software Configuration