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rfjakob

37 karma · joined October 6, 2015

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rfjakob··on Imaging mounted disk volumes under duress
I think I saw Oracle mentioned earlier, this has some info about the VSS integration. It's called 'Oracle VSS Writer': https://docs.oracle.com/database/121/NTQRF/vss.htm#BEIJJCAE

I guess MS-SQL does something similar, and that does seem useful beyond what LVM does.

Also VSS apparently can offload the snapshotting to a SAN ('VSS Hardware Provider'): https://docs.microsoft.com/en-us/windows-server/storage/file...

rfjakob··on Imaging mounted disk volumes under duress
For user application it does not signal anything I guess, but I'm not sure if that's important for databases. Databases are usually crash-consistent, which is equivalent to a snapshot.

However, it does signal to the filesystem, quoting https://manned.org/fsfreeze.8 :

       fsfreeze is unnecessary for device-mapper devices. The device-mapper (and
       LVM) automatically freezes a filesystem on the device when a snapshot
       creation is requested. For more details see the dmsetup(8) man page.
rfjakob··on Imaging mounted disk volumes under duress
I'm not sure I follow here. Linux does have LVM, what's the problem with it?

That's also what the article says: If you have LVM, you don't need any special tool.

rfjakob··on The pitfalls of using SSH-agent, or how to use an agent safely
From man ssh-add:

     -c      Indicates that added identities should be subject to confirmation be‐
             fore being used for authentication.  Confirmation is performed by
             ssh-askpass(1).  Successful confirmation is signaled by a zero exit
             status from ssh-askpass(1), rather than text entered into the re‐
             quester.
I'm a bit surprised that this is not mention in the article, as this seems very useful to make exploits more difficult.
rfjakob··on The Fed stalls the creation of a bank with a novel business model
Don't banks take deposits because they want to lend?
rfjakob··on The Fed stalls the creation of a bank with a novel business model
I'm not really sure what you mean. The Bank of England article you linked says:

> that would leave the buyer’s bank with fewer reserves and more loans relative to its deposits than before. [...] > By attracting new deposits, the bank can increase its lending without running down its reserves, as shown in the third row of Figure 2.

So actually the banks need deposits to hand out loans. What you are saying is that the deposits get a new label before handing them out as loans?

rfjakob··on In defence of swap: common misconceptions
There's a userspace daemon that does that: https://github.com/rfjakob/earlyoom (I am the author)