different essential ideals

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Does there exist a $C^*$ algebra which has more than one essential ideal?If there exists such a $C^*$ algebra ,suppose $I,J$ are two different essential ideals,$I\subset J$,can we compare the multiplier algebras $M(I)$ and $M(J)$?

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Take $A=C[0,1]$. For each $x\in[0,1]$, $$ I_x=\{f:\ f(x)=0\} $$ is an essential ideal. So you have uncountably many of them. And there are more, because finite intersections of essential ideals are again essential.

For the inclusion, one could have $M(I)\subset M(J)$ if $I\subset J$ if $I$ has an approximate unit for $J$; this doesn't require them to be ideals nor essential. I'm not sure what can be said in general. .