Have you noticed a sequence of KERNEL messages in your Syslog coming from an AP
and which all begin with "AG7100"? The sequence looks like this:
Feb 20 10:51:42 2015 10.9.210.29 KERNEL(AP-name@10.2.3.4): AG7100: unit 0 phy is up...RGMii 1000Mbps full duplex
Feb 20 10:51:42 2015 10.9.210.29 KERNEL(AP-name@10.2.3.4): AG7100: pll reg 0x18050010: 0x110000 AG7100: cfg_1: 0x1ff0000
Feb 20 10:51:42 2015 10.9.210.29 KERNEL(AP-name@10.2.3.4): AG7100: cfg_2: 0x3ff
Feb 20 10:51:42 2015 10.9.210.29 KERNEL(AP-name@10.2.3.4): AG7100: cfg_3: 0x18001ff
Feb 20 10:51:42 2015 10.9.210.29 KERNEL(AP-name@10.2.3.4): AG7100: cfg_4: 0xffff
Feb 20 10:51:42 2015 10.9.210.29 KERNEL(AP-name@10.2.3.4): AG7100: cfg_5: 0xfffef
Feb 20 10:51:42 2015 10.9.210.29 KERNEL(AP-name@10.2.3.4): AG7100: done cfg2 0x7215 ifctl 0x10000 miictrl 0x22
What makes this sequence of messages interesting is that they repeat throughout the day
and the very first message will randomly change between "1000Mbps" and "100Mbps".
You may recognize this sequence as part of the normal boot-up sequence of an AP. Yet when
you investigate, e.g. "show ap debug crash-info ap-name AP-name", there is no evidence
of the AP crashing and very little else to assist with troubleshooting. If you replaced
the AP and tried a different port and the problem persists, consider your cabling.
Remember, Gigabit needs 4-pair while 100Mbps only needs two pair. The twisted-pair
cabling may exist on the margin between a reliable and unreliable Gigabit cable and the AP
is just reacting to what it sees on the cable. This happened to us with ArubaOS 6.4.2.4
and an AP-105.
A cable-tester, such as as a Fluke LinkRunner, should show the problem. In our case,
after fixing the cabling and certifying it for CAT5e, the messages stoppd and
the AP stayed in Gigabit mode without any more problems.
While troubleshooting the original problem we also noticed several other APs in the
building that were operating at 100Mbps instead of the expected Gigabit. They were
not sending out error messages, they simply booted at 100Mbps and stayed there.
These APs also had bad cables and the problem was resolved with new cabling.
I have submitted this as a "discussion" item on the Airheads Community in case others
may benefit from the information. I have no idea which "Location" or "Board" this should
be posted to. When I searched for information on these error messages
I came up empty. Ideally, I should be able to create a KB article. Since Aruba does
not allow the user community to contribute KB articles, this was the best approach
to sharing that I could find. If there is a better approach to sharing, please let me know.