We have several of the SPA5xx models working nicely with 1 sidecar and Asterisk, and they even survive better than many competitor products under load, but we only seem to be able to get them working well with one sidecar.
If a second sidecar is added we get 2 problems:
1) Only about 59 BLF subscriptions are possible. The last 4 to 6 keys stay yellow and the Web UI shows they are correctly configured, but are unsubscribed. We know that the subscriptions are possible as they work on another vendor's equipment.
2a) The spa525g reboots after about a minute if more than 60 BLF subscriptions are configured.
2b) The spa504g cannot manage sustained BLF load with the 2nd sidecar configured. It hangs after a number of hours.
We also tried this with an SPA962 and SPA932 sidecar - This also only allows about 59 subscriptions, but appears to remain stable.
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