CCP §1162: (a) Except as provided in subdivision (b), the notices required by Sections 1161 and 1161a may be served by any of the following methods: (1) By delivering a copy to the tenant personally.

(a) Except as provided in subdivision (b), the notices required by Sections 1161 and 1161a may be served by any of the following methods: (1) By delivering a copy to the tenant personally. (2) If he or she is absent from his or her place of residence, and from his or her usual place of business, by leaving a copy with some person of suitable age and discretion at either place, and sending a copy through the mail addressed to the tenant at his or her place of residence. (3) If such place of residence and business cannot be ascertained, or a person of suitable age or discretion there can not be found, then by affixing a copy in a conspicuous place on the property, and also delivering a copy to a person there residing, if such person can be found; and also sending a copy through the mail addressed to the tenant at the place where the property is situated. Service upon a subtenant may be made in the same manner. (b) The notices required by Section 1161 may be served upon a commercial tenant by any of the following methods: (1) By delivering a copy to the tenant personally. (2) If he or she is absent from the commercial rental property, by leaving a copy with some person of suitable age and discretion at the property, and sending a copy through the mail addressed to the tenant at the address where the property is situated. (3) If, at the time of attempted service, a person of suitable age or discretion is not found at the rental property through the exercise of reasonable diligence, then by affixing a copy in a conspicuous place on the property, and also sending a copy through the mail addressed to the tenant at the address where the property is situated. Service upon a subtenant may be made in the same manner. (c) For purposes of subdivision (b), “commercial tenant” means a person or entity that hires any real property in this state that is not a dwelling unit, as defined in subdivision (c) of Section 1940 of the Civil Code, or a mobilehome, as defined in Section 798.3 of the Civil Code.