MavEtJu's Distorted View of the World - 2008-02

Posted on 2008-02-28 15:00:00, modified on 2008-02-28 15:15:00
Tags: VegaStream, SNMP, Numbers

VegaStream has some very nice ATAs and T38 devices (still), but after the upgrade to VEGA400_R082S017 (8.2.17) every two and a half day their system.sysUptime counter gets resetted:

> Host  : sjh-vega400
> Output: Uptime is less than an hour! (328.61 seconds)
> Date  : 2008-02-28 14:21:08

According to Nagios, this happens every two and a half days:

• 2008-02-28 14:19:03
• 2008-02-26 02:37:41
• 2008-02-23 15:00:18
• 2008-02-21 03:22:56

The device doesn't reboot, the sysUpTime count just goes back to zero. Device itself says it's up for 9 days.

About 2 days, 11 hours, 37 minutes, 62 seconds.
214682 seconds...
0x3469a...

Update
Thanks to callum on irc.oz.org/#bugs : 2 ^ 31 / 10,000, or an overflow of the signed counter of the number of 100 microseconds.

Posted on 2008-02-18 16:00:00
Tags: VegaStream, Networking, SNMP

[~/snmp] root@lizard>snmpwalk -v 1 -c public test-vega
RFC1213-MIB::sysDescr.0 = STRING: "Vegastream IP Telephony Gateway (VEGA-6x4)"
RFC1213-MIB::sysObjectID.0 = OID: RFC1155-SMI::enterprises.4686.11
DISMAN-EVENT-MIB::sysUpTimeInstance = Timeticks: (305772277) 35 days, 9:22:02.77
RFC1213-MIB::ifNumber.0 = INTEGER: 2
RFC1213-MIB::ifIndex.1 = INTEGER: 1
RFC1213-MIB::ifIndex.2 = INTEGER: 2
RFC1213-MIB::ifDescr.1 = STRING: "VS LAN Port 1"
RFC1213-MIB::ifDescr.2 = STRING: "VS LAN Port 2"
RFC1213-MIB::ifType.1 = INTEGER: ethernet-csmacd(6)
RFC1213-MIB::ifType.2 = INTEGER: ethernet-csmacd(6)
RFC1213-MIB::ifMtu.1 = INTEGER: 1514
RFC1213-MIB::ifMtu.2 = INTEGER: 1514
RFC1213-MIB::ifSpeed.1 = Gauge32: 104857600
RFC1213-MIB::ifSpeed.2 = Gauge32: 10485760

104857600 is 100 * 1024 * 1024, or their idea of an 100 Mbps ethernet.

Posted on 2008-02-15 20:00:00
Tags: CityRail, RSS

The train is late, the train is cancelled, the train has been late, the train has been cancelled. Nobody looks it, and knowing it in advance is a major pro.

CityRail does provide this information at http://www.cityrail.info/latest_news/content.jsp, but it doesn't have a historical overview so you don't know if it is getting worse or that it is slowing down.

At http://www.mavetju.org/cityrail/delays/rss.php you can find an RSS feed with all issues, still active and finished, updated once every five minutes.

Note: Sometimes you see what might look like double entries in the overview. Most likely in this case is that the Posted date has been changed at the CityRail website.

Posted on 2008-02-10 20:00:00
Tags: Networking, DNS, dnstracer

The first, alphabetically sorted, DNS root servers has been assigned an IPv6 address. It is not the first one, relatively speaking: f.root-servers.net, h.root-servers.net, j.root-servers.net, k.root-servers.net and m.root-servers.net had one before a.root-servers.net. So what?

Since it's the first letter in the alphabet, programs will use the a.root-servers.net as their first source to get information from the DNS system. So does dnstracer, one of my tools to gather information about possible issues with the DNS system.

To start dnstracer, you can give it an initial DNS server where it should start its queries with regarding to a certain domain. To prevent you from having to enter a.root-servers.net, you can just give the string ., which will be replaced internally with a.root-servers.net. That part works fine.

Dnstracer also has an option to disable IPv6 queries during the diagnostics phase. That part also works fine.

What didn't work fine was the part which did do the initial DNS server, the a.root-servers.net and the option to disable IPv6 queries: It didn't disable the IPv6 query for the initial DNS server. The result? The initial request for a.root-servers.net always returned the IPv6 address, even if you disabled the IPv6 queries. And since 95+% of the popuplation of this planet still doesn't have access to an IPv6 network, the tool didn't work anymore.

Well, it worked if you used b.root-servers.net instead of ., but it needed to fixed properly too.

The fixed version can be found at http://www.mavetju.org/download/dnstracer-1.9.tar.gz, the FreeBSD port is updated.