ss7box redundancy is the next big feature in the works. Now that SMG clustering is in the field and working, some larger systems are being designed. As predicted, those system designers quickly spot a single ss7box as a single point of failure. The solution is to deploy two ss7box acting as a single entity - so called redundancy. If one ss7box is lost then operations continue without interruption.
A redundant ss7box configuration minimizes interruptions during upgrades because one ss7box can serve on-going operations while the other is off-line and being updated. Then the updated ss7box serves operations and other ss7box is updated. Finally, both updated ss7box are put online and normal redundant operations resume.
We found a flaw in GRS processing in the past two weeks. The fix required enhancing GRS processing so that each trunk group has its own GRS queue. The ehancement is used if GRS processing gets stuck in ss7boost and the remote end keeps repeating requests for GRS. In this scenario, GRS requests are queued and after N queued GRS, the GRS queue overflows. When this happens, the GRS queue is cleared, all circuits in the trunk group associated with the GRS queue are put into quarantine, and subsequent GRS for the trunk group are ignored until all circuits in the trunk group have exited quarantine. The persistent nature of the GRS protocol ensures that a GRS will arrive after the GRS queue clearing protocol has completed. As ss7boost matures, more of these complex, self-healing protocols are being implemented which make SMG more robust and reliable. I makes SMG easier to use and maintain for users and support staff.
The smgcfg.py script is helping users and support staff create, update, and maintain SMG configurations. With the introduction of SMG clustering it became evident that hand editing text configuration files was unwieldy. With smgcfg.py the entire configuration for a node is entered in a single spreadsheet tab. We are using Googledoc spreadsheets to enable editable sharing of SMG configuration spreadsheets on a worldwide basis.
Check out the Twitter feed on this blog. Small increments of progress are reported in that media stream