Ineligible means that the court won't set bail so he must remain in custody. There are many reasons for this so I cannot specifically tell you the reason in this particular case.
The response above is not intended as legal advice since it’s impracticable to provide thorough, accurate advice based upon the query without additional details. It is highly recommended that one should seek advice from a criminal defense attorney licensed in your jurisdiction by setting up a confidential meeting. Moreover, this response does not constitute the creation of an attorney-client relationship since this message is not a confidential communication because it was posted on a public website, thereby publicly disclosing the information, which is another reason to setup a confidential meeting with an attorney.
If in Rancho, I am almost positive it was due to priors-previous criminal charges and or convictions. The court thinks he will run or the court does not think it to be a good idea to afford him the opportunity to commit more crimes. Mind you, I do not know what he is charged with now nor his criminal background. Make sure he has counsel.
Means your illegal boyfriend with the outstanding warrant is not going anywhere. If he failed to appear and doesn't have a good excuse for his non-appearance, he's not getting out. Moreover, if he's illegal, ICE probably has a immigration hold on him and he will be held for them once his case is completed. ICE will then decide whether to deport him or let him go with a notice to appear for an immigration hearing.