I dont' think that cloud is unsafe , and unpredictable , as now a days companies like Amazon , ibm are providing cloud services with high security provisions , and i do agree with Nane Kratzke, its all depends on use case and company

Provides high availability and reliability of Data in Case of failure/crash of Systems at site. But to use cloud or other solution is major concern. Now private cloud and hybrid cloud high security.

Christian Benjamin Ries> Why you are so sure ""never ever" it is an option to backup using cloud and private cloud and hybrid cloud high security. as  we know that .

Nane Kratzke > big company  i.e google , MS, FB and so on .

for use case to backup their data.

With thanks 

Jimesh Rakesh Prajapati > I agree with you , cloud services in use already and some of these services are secure .

Thanks 

Deepak Garg > i'am not sure of Provides high availability and reliability of Data in Case of failure/crash of Systems at site.what do you mean of site !!!

with thanks 

yes, w.r.t. the observation, that more and more services and applications are offered as cloud services. so most of the data will naturally already reside there.

Personally, I do so using one of the big cloud providers...

Of course, the answer to this question depends on company outlook and requirements. Of the organizations that elect to utilize cloud services, their involvement may be a little (just using Salesforce to track campaigns) or a lot (no local resources and everything running in someone else’s cloud data center). You don’t have to go “all in” on the cloud, of course – there are private, public and hybrid cloud solutions to mix and match with.

"Depends ..." is the answer.  But in the context of "Big companies that has DC that consume cloud services (not big Cloud Service Provider)", normally they don't backup all their data into cloud due to many reasons like security, connectivity, compliance, government regulatory requirements etc. (depend on what types of cloud deployments also).  But some big companies do backup some non-critical data into cloud or upload their apps like web or business logic to certain extend to cloud but data remain in more secured DC.

I think many companies will keep its data centers for many reasons one of them is security issues.

By cloud, do you mean public or private cloud?

While companies and governments are not likely to be moving to public cloud (for security/legal issues), the trend is I think to setup a private, enterprise-wide cloud. The company will still have its Data Center, but this Data Center will be operated like a private cloud to address the needs of all the departments, divisions, etc. worldwide within the company,