Cha'Xirrac is a planet near Cardassian Union space and the homeworld of the Xirri civilization. The planet was known as Armageddon as several impacts from comets had damaged the atmosphere of the planet and the ecosystem. The Federation designation of the planet was KDZ-E25F before the existence of the Xirri became known.
In the year 2372, several Klingons were banished to Cha'Xirrac, including members of the House of Vrag and the House of Gordek. To obtain supplies from the Cardassians, Gordek and his people began to extract geset from the planet. (DS9 - Day of Honor novel: Armageddon Sky)