How to ignore error and continue infinite stream?

You may want to use one of the error handling operators.

• onErrorResumeNext( ) — instructs an Observable to emit a sequence of items if it encounters an error
• onErrorReturn( ) — instructs an Observable to emit a particular item when it encounters an error
• onExceptionResumeNext( ) — instructs an Observable to continue emitting items after it encounters an exception (but not another variety of throwable)
• retry( ) — if a source Observable emits an error, resubscribe to it in the hopes that it will complete without error
• retryWhen( ) — if a source Observable emits an error, pass that error to another Observable to determine whether to resubscribe to the source

Especialy retry and onExceptionResumeNext look promising in your case.