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seen Apr 11 at 18:28

Moderator♦ on Security StackExchange

Production Engineer at Facebook

Twitter: @jbferland


Feb
20
comment Privileges for ifconfig
... but that doesn't answer if there's a way to run it without being root. The Linux capabilities model is the defining matter in that. While root is traditionally granted these rights, other processors or users can be blessed with capabilities such as through SELinux contexts or as demonstrated by Celada using setcap (being rather like making a executable setuid, but for capbilities)
Feb
8
comment /tmp was 1.8Gb; removing files older than 8 days has deleted only ~300mb.. what's using so much space?
@dunc grep /tmp/ test
Feb
8
comment How to track traffic tidal wave on Amazon EC2 instance?
Sounds like you might need a consultant if your load spikes almost instantly to far beyond what a machine can handle unless you're keeping systems on idle standby, have a static content failover, or are otherwise able to scale up almost instantly.
Feb
7
comment find command + enable Exit status to be diff then 0 when not match
The basic problem comes from redirecting stderr to /dev/null. If you're running this as a scripted job, you'd never be aware of any errors even if the script did find a file. You wouldn't be aware that it was perhaps missing files it couldn't access due to permissions issues such as directories that don't have read permissions set. Remove that and let the parent script discard stderr if it is appropriate.
Feb
7
comment How to stop every incoming traffic except from 1 ip, on an ubuntu server
An answer should provide an answer within itself and use links as supporting references. Your answer post doesn't provide any information without following links and one of the links is a Google search. In this particular case, a concrete answer to the question should have been posted.
Feb
7
comment How to stop every incoming traffic except from 1 ip, on an ubuntu server
possible duplicate of Iptables: How to allow only one ip through specific port?
Feb
6
comment Executables location
... or if users launch an application that they can then launch explorer from.
Feb
6
comment find command + enable Exit status to be diff then 0 when not match
In this case, if find had an error it would print the result to /dev/null, return a non-zero exit, and then have that fixed to 0 by the test command.
Jan
30
comment ~18m files total files EXT4 poor performance, any advice?
Is dir_index enabled? sudo tune2fs -l /dev/sda1 | grep dir_index
Jan
18
comment Does nova support pxe boot?
What I'm saying is that this doesn't tell anybody else who looks at your question how they might solve the problem for themselves.
Jan
18
comment Does nova support pxe boot?
What's the line you added?
Jan
16
comment Does nova support pxe boot?
@EvanLi If you're using a "flat" network and providing your own DHCP service, then yes -- an appropriate boot image supporting PXE can be used and you'll have PXE booting.
Jan
16
comment Does nova support pxe boot?
@EvanLi You'd have to modify the source code of the product to provide an interface for PXE options to be entered and appropriate mechanism of passing those options to the underlying dnsmasq process.
Jan
16
comment Does nova support pxe boot?
@MichaelHampton The surrounding framework of the cloud needs to support passing those options, though. I'm working on implementing that in a related product that uses KVM, actually.
Jan
16
comment Does nova support pxe boot?
Doesn't the PXE process need appropriate DHCP options? Unless OpenStack's system allows setting those parameters, I'm not sure this will help.
Jan
16
comment Does nova support pxe boot?
Note, cross-posted at stackoverflow.com/q/14349812/90322
Jan
10
comment Windows Server 2003 permissions not working properly and I can't fix it
This is hard to follow in such long narrative form.
Dec
18
comment Linux IPv6: DHCP and /127 prefixes
@fukawi2 I am the OP. The A flag is not set.
Dec
17
comment Linux IPv6: DHCP and /127 prefixes
There are two flags in a router advertisement: the "A" flag (use SLAAC), and the the "M" flag on (use DHCPv6). A is off, M is on. Router Advertisements must be in place regardless of the subnet size because DHCPv6 packets don't include router information the way that DHCPv4 packets do, nor do they include subnet prefix sizes.
Dec
7
comment Bacula stops writing to disk volume after 2GB
Asker (apparently) commented (via an attempted suggested edit) that editing etc/autofs.master from backup-pool -nfsvers=2 server:/path to backup-pool -fstype=nfs4 server:/path worked. See serverfault.com/review/suggested-edits/43385