it's custom, designed by Dublin's office of Enterprise IG.

is there a font looks like the font used in eircom?

The 'e' is very FF Dax.

I was going to edit my post prior to seeing your second question, saying that, since there are only a few letters involved (and obviously the most prominent in the design is the "small cap" "R") any sans like say Legacy Sans Or Ocean Sans would get you there with a couple of tweaks.