Updating distributed storage network software

1. A method of updating software in a dispersed storage network (DSN), where the DSN includes a plurality of dispersed storage (DS) units having respective software, the method comprising:

identifying, by one DS unit of the plurality of DS units, a subset of other DS units of the plurality of DS units, wherein the one DS unit and the subset of other DS units comprise a set of DS units of the plurality of DS units that store encoded data slices associated with a storage vault, and wherein a decode threshold number of DS units is needed to reconstruct data encoded in the encoded data slices;

determining, by the one DS unit, that a number of available DS units in the set of DS units is greater than the decode threshold number of DS units based on an update status of the set of DS units; and

updating, by the one DS unit, the respective software of the set of DS units including the respective software of the one DS unit itself, while maintaining availability of the decode threshold number of DS units of the set of DS units to service access requests to the data encoded in the encoded data slices.

2. The method of claim 1 , wherein updating the respective software of the set of DS units is based on a status of a software update, and wherein the status of the software update includes one or more of a mandatory critical status, a mandatory non-critical status, and an optional status.

3. The method of claim 1 , wherein the update status includes one or more of available, unavailable, already updated, and not already updated.

4. The method of claim 1 , further comprising:

identifying, by the one DS unit, a plurality of storage vaults supported by the one DS unit, wherein the plurality of storage vaults includes the storage vault;

identifying, by the one DS unit, a plurality of subsets of other DS units of the plurality of DS units, wherein the plurality of subsets of other DS units includes the subset of other DS units, wherein the one DS unit and each of the plurality of subsets of other DS units comprise each of a plurality of sets of DS units that support one of the plurality of storage vaults, and wherein the plurality of sets of DS units includes the set of DS units; and

updating, by the one DS unit, the respective software of the set of DS units, including the respective software of the one DS unit itself, while maintaining availability of decode threshold numbers of DS units of each set of DS units in the plurality of sets of DS units.

5. The method of claim 4 , wherein another set of DS units of the plurality of sets of DS units stores other encoded data slices associated with another one of the plurality of storage vaults, wherein the decode threshold number of DS units is needed to reconstruct other data encoded in the other encoded data slices, further comprising:

determining, by the one DS unit, that another number of available DS units in the another set of DS units is equal to the decode threshold number of DS units; and

determining, by the one DS unit, to update the respective software of the another set of DS units later in response to determining the another number of available DS units is equal to the decode threshold number of DS units.

6. The method of claim 4 , wherein another set of DS units of the plurality of sets of DS units stores other encoded data slices associated with another storage vault, wherein another decode threshold number of DS units is needed to reconstruct other data encoded in other encoded data slices, and wherein the another decode threshold number of DS units is different from the decode threshold number of DS units, further comprising:

determining, by the one DS unit, that another number of available DS units in the another set of DS units is greater than the another decode threshold number of DS units.

7. The method of claim 6 , further comprising:

determining a priority for each of the plurality of storage vaults, wherein a first one of the plurality of storage vaults corresponding the set of DS units has a first priority, and wherein a second one of the plurality of storage vaults corresponding to the another set of DS units has a second priority.

8. The method of claim 7 , further comprising:

updating, by the one DS unit the respective software of the another set of DS units while maintaining availability of the another decode threshold number of DS units of the another set of DS units, wherein the set of DS units is updated before the another set of DS units in response to the first priority being greater than the second priority.

9. A dispersed storage (DS) unit of a dispersed storage network (DSN), where the DSN includes a plurality of DS units, including the DS unit, having respective software, the DS unit comprising:

a communications interface;

a memory; and

a computer processor;

where the memory includes instructions for causing the computer processor to:

identify a subset of other DS units of the plurality of DS units, wherein the DS unit and the subset of other DS units comprise a set of DS units of the plurality of DS units that store encoded data slices associated with a storage vault, wherein a decode threshold number of DS units is needed to reconstruct data encoded in the encoded data slices;

determine that a number of available DS units in the set of DS units is greater than the decode threshold number of DS units based on an update status of the set of DS units; and

update the respective software of the set of DS units, including the respective software of the DS unit itself, while maintaining availability of the decode threshold number of DS units of the set of DS units to service access requests to the data encoded in the encoded data slices.

10. The DS unit of claim 9 , wherein the memory further comprises instructions for causing the computer processor to update the respective software of the set of DS units based on a status of a software update and wherein the status of the software update includes one or more of a mandatory critical status, a mandatory non-critical status, and an optional status.

11. The DS unit of claim 9 , wherein the update status includes one or more of available, unavailable, already updated, and not already updated.

12. The DS unit of claim 9 , wherein the memory further comprises instructions for causing the computer processor to:

identify a plurality of storage vaults supported by the DS unit, wherein the plurality of storage vaults includes the storage vault;

identify a plurality of subsets of other DS units of the plurality of DS units, wherein the plurality of subsets of other DS units includes the subset of other DS units, wherein the DS unit and each of the plurality of subsets of other DS units comprise each of a plurality of sets of DS units that support one of the plurality of storage vaults, and wherein the plurality of sets of DS units includes the set of DS units; and

update the respective software of the set of DS units, including the respective software of the DS unit itself, while maintaining availability of decode threshold numbers of DS units of each set of DS units in the plurality of sets of DS units.

13. The DS unit of claim 12 , wherein another set of DS units of the plurality of sets of DS units stores other encoded data slices associated with another one of the plurality of storage vaults, wherein the decode threshold number of DS units is needed to reconstruct other data encoded in the other encoded data slices, and wherein the memory further comprises instructions for causing the computer processor to:

determine that another number of available DS units in the another set of DS units is equal to the decode threshold number of DS units.

14. The DS unit of claim 13 , wherein the memory further comprises instructions for causing the computer processor to:

determine to update the respective software of the another set of DS units later in response to determining the another number of available DS units is equal to the decode threshold number of DS units.

15. The DS unit of claim 12 , wherein another set of DS units of the plurality of sets of DS units stores other encoded data slices associated with another storage vault, wherein another decode threshold number of DS units is needed to reconstruct other data encoded in other encoded data slices, wherein the another decode threshold number of DS units is different from the decode threshold number of DS units, and wherein the memory further comprises instructions for causing the computer processor to:

determine that another number of available DS units in the another set of DS units is greater than the another decode threshold number of DS units.

16. The DS unit of claim 15 , wherein the memory further comprises instructions for causing the computer processor to:

determine a priority for each of the plurality of storage vaults, wherein a first one of the plurality of storage vaults corresponding the set of DS units has a first priority, and wherein a second one of the plurality of storage vaults corresponding to the another set of DS units has a second priority.

17. The DS unit of claim 16 , wherein the memory further comprises instructions for causing the computer processor to:

update the respective software of the another set of DS units while maintaining the availability of the another decode threshold number of DS units of the another set of DS units, wherein the set of DS units is updated before the another set of DS units in response to the first priority being greater than the second priority.

18. A method of updating software in a dispersed storage network (DSN), where the DSN includes a plurality of dispersed storage (DS) units, each of the plurality of DS units having corresponding software, the method comprising:

identifying, by one DS unit of the plurality of DS units, a subset of other DS units of the plurality of DS units, wherein the one DS unit and the subset of other DS units comprise a set of DS units of the plurality of DS units that store encoded data slices associated with a storage vault, and wherein a decode threshold number of DS units is needed to reconstruct data encoded in the encoded data slices;

determining, by the one DS unit, that a number of available DS units in the set of DS units is greater than the decode threshold number of DS units based on an update status of the set of DS units; and

updating, by the one DS unit, the corresponding software of the set of DS units, while maintaining availability of the decode threshold number of DS units of the set of DS units to service access requests to the data encoded in the encoded data slices.

19. The method of claim 18 , wherein updating the corresponding software of the set of DS units is based on a status of a software update, and wherein the status of the software update includes one or more of a mandatory critical status, a mandatory non-critical status, and an optional status.

20. The method of claim 18 , wherein the update status includes one or more of available, unavailable, already updated, and not already updated.