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7900 Series Sidecars -- They don't work?

We've had problems with 7900 series sidecars (and phones with sidecars on them) for some time. Recently this has been worse, and has given me the opportunity to research this across our customer base.

What I found:

7975 + (2)7916-24: We have 4 of these, spread across 3 clients. EVERY SINGLE ONE REBOOTS ON A REGULAR BASIS. Sometimes during calls, sometimes just randomly. Two of the three clients are experiencing it more often, but all of the phones reboot randomly. Firmware upgrades/downgrades do nothing.

7960 + (1)7914: There seems to be a bug where the labels on the sidecar are blank. We are experiencing this on 4 of them, spread across two clients.

We are not alone in this either:

If you rearrange buttons... different ones go blank. We currently have a case open with TAC -- they have no clue. They requested we run "debug ephone detail mac xxx"... this crashed the customers phone system during business hours. In fact -- I have seen that debug crash the UC500 almost every time I have ever used it. (5+) I love it when even the debugs are buggy.

We tend to install more SPA phones (mostly due to cost), so there are relatively few of these in our install base. At this point it appears that every 7900 series sidecar we are aware of (or the phone they are attached to) are NOT stable. Has anyone had similar experiences? Or the opposite?



Definitely this is strange with port mirroring.

Maybe PoE is making some problems there. The current is not sufficient from time to time. Did you notice from the logs reboots of the phone when the building is empty?

Best regards,



and close them). Still no resolution. I STILL have a L2 case open on the issue. Currently they want a permanent packet capture server installed at the customer site to do long-running packet capture of the phones. This is insane.

It's unpleasant, but not insane. You have to provide TAC with what all want, and then on your side demand that you deal with best the esclation team (full CCIE level), or directly with engineering at times. That is the only possible way to have nasty bugs identified and fixed.


I am having the same issue with a UC540 and 3 7914 sidecars. All 3 sidecars will not show anything for the last 3 buttons in regards to the label. They do the show the phone icon and status on the right. I have upgraded everything possible to the latest versions. I have even had this issue transcend from one UC540 to another one (I had to have one replaced due to odd issue with wan port). I did restore the config so it could be in the config but I don't see how. I will try to delete / create CNF files and let you know my results from that.

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