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bio website gcarrier.fr
location San Francisco, CA
age 26
visits member for 2 years, 5 months
seen Dec 12 at 22:45

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Jul
7
answered ULogd2.x - Documents - IPFIX data generation
Jul
7
comment ULogd2.x - Documents - IPFIX data generation
[follow up] I would use libnetfilter_conntrack in 2 separate processes: 1. to grab all the events I'm interested into (multiple contexts to allow for complex filtering logic as their bsf usage is rather limited) and publish them on a zeromq socket, reencoded in msgpack (obviously with network endianness). 2. to periodically go through all connections and publish a snappy-compressed msgpacked list. That way I can have a good view of the current connections on a host even if the other process dies, or connections are started before it, and get traffic counters reasonably often.
Jul
7
comment ULogd2.x - Documents - IPFIX data generation
Unfortunately it'd have to be more complete then go through a code review before I can publish it. I don't target any IPFIX support on the machines but would rather take care of that centrally as I want a minimal communication layer on the hosts that can adapt to different types of information. I'll do the deduplication given I'll see many connections multiple times (from both machines when within my infrastructure, through 1 firewall in some contexts, through 2 firewalls for many cross-DC connections), and IPFIX tooling can't be as precise as some information will be lost in the translation.
Jul
7
comment Is there an way to get the top level classes included in a puppet node?
You can't have a command running on the client giving you the information, as the external node classifier and manifests are only known by the puppetmaster and never exposed to the puppet agent (only the compiled manifests are). So you'll need a trick like mine in your manifests, which is compiled by the puppetmaster then provided to the agent.
Jul
6
answered SSH equivalent of .profile/.bashrc
Jul
6
answered mkisofs - Floppy Image to Disk Image
Jul
6
revised hosts.allow and hosts.deny WHM Host Access Control - what if my IP changes?
added 710 characters in body
Jul
6
answered Gerrit replication, reject HostKey
Jul
6
revised hosts.allow and hosts.deny WHM Host Access Control - what if my IP changes?
added 396 characters in body
Jul
6
answered hosts.allow and hosts.deny WHM Host Access Control - what if my IP changes?
Jul
6
awarded  Organizer
Jul
6
revised ULogd2.x - Documents - IPFIX data generation
edited tags
Jul
6
comment ULogd2.x - Documents - IPFIX data generation
I have a project to collect nf_conntrack_netlink data and aggregate it centrally, but if an efficient solution based on ulogd exists I'd love to hear about it!
Jul
6
comment Enabled hyperthreading - causes qthread creation error on Ubuntu Precise 64 bit
OK, then it looks like a kernel bug. Can we have uname -a?
Jul
6
revised DNS Help (CNAMEs and A Records)
added 9 characters in body
Jul
6
answered DNS Help (CNAMEs and A Records)
Jul
6
revised Which OS/distributions have 64-bit kernel and 32-bit userspace?
added 3 characters in body
Jul
6
comment Which OS/distributions have 64-bit kernel and 32-bit userspace?
If you do have a lot of pointers, they are double the size and will end up taking quite some memory. What your apps allocate you'll lose in filesystem cache, you'll also get get more cache misses (quite expensive), worse NUMA balancing (I'm fetching quite far here he he).
Jul
6
awarded  Commentator
Jul
6
comment Ubuntu - why would /var/log/dmesg stop updating after boot? does not show panic/cpu_hung errors which the console shows
You also need kern.* /var/log/dmesg (and obviously not commented).