Hi all, I've got a strange problem with a customer's phones. They've got a bunch of Grandstreams that seem to be rock solid... until 7:00pm. At 7:00, some of the phones become unavailable, and stay down. Call quality is solid almost all the time. But right at 7:00, things go bad. Only some of the phone lines go down and they stay down until the phone is rebooted. I'm not even sure what to look for when I go to the site. Any ideas? -- Take care and have fun, Mike Diehl.
On Thu, 2011-07-21 at 17:13 -0600, Mike Diehl wrote:> Hi all, > > I've got a strange problem with a customer's phones. > > They've got a bunch of Grandstreams that seem to be rock solid... until > 7:00pm. At 7:00, some of the phones become unavailable, and stay down. Call > quality is solid almost all the time. But right at 7:00, things go bad. Only > some of the phone lines go down and they stay down until the phone is > rebooted. > > I'm not even sure what to look for when I go to the site. Any ideas? >Are the phones running on the same connection as the computers/servers? If so, are they doing any scheduled backups? Ish -- Ishfaq Malik Software Developer PackNet Ltd Office: 0161 660 3062
On Thu, Jul 21, 2011 at 7:13 PM, Mike Diehl <mdiehl at diehlnet.com> wrote:> Hi all, > > I've got a strange problem with a customer's phones. > > They've got a bunch of Grandstreams that seem to be rock solid... until > 7:00pm. At 7:00, some of the phones become unavailable, and stay down. > Call > quality is solid almost all the time. But right at 7:00, things go bad. > Only > some of the phone lines go down and they stay down until the phone is > rebooted. > > I'm not even sure what to look for when I go to the site. Any ideas? > >Many years ago, in my college days, the network in one building would fail around a certain time every day. The sun would hit the network closet around the same time every day in the summer, causing the equipment to overheat and temporarily fail. I would go there and observe everything which happens at 7:00. Maybe it's something that a cleaning service inadvertently does, like faulty wiring + a vacuum cleaner. -M -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.digium.com/pipermail/asterisk-users/attachments/20110722/4b332a0f/attachment.htm>
> They've got a bunch of Grandstreams that seem to be rock solid... until > 7:00pm. At 7:00, some of the phones become unavailable, and stay down. Call > quality is solid almost all the time. But right at 7:00, things go bad. Only > some of the phone lines go down and they stay down until the phone is > rebooted. > > I'm not even sure what to look for when I go to the site. Any ideas?I'd look to see if there are any electrical circuits (lights, fans, etc.) which are on a timer of some sort, and are automatically powered off at 7 PM. If somebody mistakenly plugged a piece of network kit into such a circuit, it would lose power at that time, and your network might end up being partitioned, or routing (switch or IP-level) might change abruptly. If (for example) the phones were being DHCP-provisioned with network numbers and a "here is your default gateway" configuration, and that gateway were to lose power, the phones would lose connectivity, and might not recover until they discarded their DHCP credentials and routing information, and broadcast for a new configuration... which would happen if they were power-cycled, or (if not then) many hours later. Similar things could happen if (for example) a janitor were to plug a floor polisher into a power circuit shared with servers or network equipment... the turn-on / turn-off power sags and spikes might knock networking gear off-line. [This is not a hypothetical example... numerous cases of this sort of thing have been reported over the years.] If these phones are being DHCP-provisioned, you might want to check each phone and see what configuration has been acquired... i.e. if it got its information from the "real" DHCP server, or from some other source. I've had network problems in the past result from people plugging some sort of "all-in-one" appliance or server into an existing net... the appliance starts trying to provide DHCP service and routing on its own. This can seriously disrupt the network... either immediately (if the appliance's configuration is incompatible with the network) or at a later time (if e.g. the appliance is acting as a router, and is then powered off).