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1h
comment Duplicate Image Searcher using Bash
If there is a specific part of this you need help with, we can help (please edit your question to ask about that one specific part)—but other than pointing to fdupes (which already does 90% of this) we're not going to write it for you.
1h
comment How to repair an overclocked microsdcard?
Please edit your question to include the dmesg lines as well as the full fsck command.
1d
comment Zswap, Zram, Zcache desktop usage scenarios
See also Ask Ubuntu's zram vs zswap vs zcache Ultimate guide: when to use which one.
1d
comment Will SSD swap improve performance?
@richard you'd need a truly massive cache to matter. And yeah, one of the battery backed RAM cards typically used for databases would be fast, but I suspect it'd be cheaper to buy a new laptop. (And they're often PCI cards, which I doubt will fit in a ultrabook).
1d
comment Access to webapp from a different machine
BTW: Those two networks shown on the chart are actual, assigned IP addresses—you shouldn't use them for your testing. Use RFC1918 space instead. They're assigned to Centro de Informatica da Universidade de Coimbra in Portugal.
1d
comment Understand HMAC authentication in case of site-to-site OpenVPN tunnel
@Gilles Finally, after all that is done, the established TLS session is used to create the encryption and authentication keys that will actually be used to encrypt and authenticate the packets. There are two possible ways this is done, controlled by --key-method. OpenVPN 1.x had one method, OpenVPN 2.x introduced (and defaults to) a new one. TLS is not used for the actual data packet encryption—it's only used for session setup. --auth only controls whether HMAC is done on the data packets. (finally done)
1d
comment Understand HMAC authentication in case of site-to-site OpenVPN tunnel
@Gilles each side can (optionally) check a CRL (--crl-verify) and do various checks on the other's identity (as asserted by the CA). There are a bunch of options for this too; and cover things like checking the certificate type (nsCertType) and key usage, the common name or full identity, etc.: --tls-verify, --ns-cert-type, --remote-cert-ku, --remote-cert-eku, --verify-x509-name. Finally, the server can require the client to present a username and password (this is normally only used when not requiring a client certificate, on e.g., large VPN providers). (continued)
1d
comment Understand HMAC authentication in case of site-to-site OpenVPN tunnel
@Gilles Anyway, in TLS mode, one side (arbitrarily, OpenVPN is typically run over UDP which doesn't have connections—though even when over TCP, it need not be the side doing the listen) is declared the server for TLS purposes in the config. Then the normal TLS exchange takes place (unless using --tls-auth, then another HMAC layer is put on top of TLS). That's controlled by the --tls-server, --tls-client, --dh, --ca, --cert, --key (or --pkcs12* options). Then, after verifying certificates (of both sides, unless --client-cert-not-required was passed),… (continued)
1d
comment Understand HMAC authentication in case of site-to-site OpenVPN tunnel
@Gilles In TLS mode, you set up a CA, generate private keys and a CSR, then use your CA to sign that. Each side has a certificate. OpenVPN by default requires each side to prove its identity (it's possible to configure it not to, but unlike with most other uses of TLS the default and normal case is both sides present certificates). And it's definitely necessary to ensure confidentiality; it's only not with e.g., a web server because the server uses some other method (e.g., username and password) to establish who its talking to. [And you can do that with OpenVPN too, actually.] (continued)
1d
comment Understand HMAC authentication in case of site-to-site OpenVPN tunnel
@Gilles --auth doesn't configure that. It only configures authenticating the packets (to protect against tampering) once the session is set up. I mention the peer authentication you're talking about in my final paragraph; that's controlled by a bunch of options, depending on the mode you're running OpenVPN in. In static key mode, the admin configured two or four shared keys (two is one for HMAC, one for encrypt; four has each side use its own HMAC and encrypt key to send). There isn't really a session set up, peer authentication is implicit in having the preshared key. (continued)
2d
comment I can not get commands to operate
For us to have any hope of answering this, please include the output of declare -p PATH in your question. Also, please use the {} button for code/plain text formatting.
2d
comment How do I process new additions to logs
logcheck
2d
comment Assistance with script on multiple hosts
(random observation, it's Friday, feeling too lazy to go through carefuly) HOSTS should be space-separated... not comma-space. You don't want those commas.
2d
comment Assistance with script on multiple hosts
@ZairaZareena there is a button at the top of the text editor that looks like {} — to use, select some text then click it. That text will be put in "code" formatting (i.e., plain text, line breaks preserved, etc.). That makes it much easier to read.
2d
comment Bypass GPG signature checks only for a single repository
@0xC0000022L yes, it should.
2d
comment Assistance with script on multiple hosts
@ZairaZareena which warning message? And please edit these details into your question.
2d
comment Have I destroyed data on drive?
Your disk should be fine now—you could run e2fsck -f (with it unmounted, of course) to be sure. And add an answer to your own question, saying how to use testdisk to fix.
2d
comment Is there a technical reason why ssh-agent lacks a sudo-like inactivity/idle timeout feature?
Another workaround: use the ControlMaster/ControlPath/ControlPersist options (see man ssh_config) for your script. At least if its only connecting to one host.
2d
comment End recording once silence is detected
Sox can read audio data from STDIN over a pipe. Just a pointer, not sure if that'll help... Or it can talk to PulseAudio, and you could do audio routing through PA.
2d
comment Problems with file system
Also, that looks like you've hit a kernel bug, a hardware issue, or maybe compiled your kernel with a feature your CPU doesn't support (picked slightly the wrong CPU—though I have no idea if that would even boot)