[CentOS] CentOS 7, as a 6in4 server
Hello, I have a VPS at a hoster where I got 3 /64 ipv6 prefixes/subnets, that are routed; one for the VPS itself - let us call this srvprefix one for the tunnel, only ::1 (server side) and ::2 (home side) are used - let us call this tunnelprefix and one for my network at home - let us call this homeprefix now I'm just in test state, a CentOS VM is the other end of the tunnel; (when the server runs well, my CentOS ZBOX will become the other end of the tunnel) at the server the eth0 device has serverprefix::1, the sit1 device has tunnelprefix::1 the routing is set with /etc/sysconfig/network-scripts/route6-sit1 tunnelprefix::2 dev sit1 homeprefix::/64 via tunnelprefix::2 dev sit1 in sysctl.conf these are set net.ipv6.conf.all.forwarding = 1 net.ipv6.conf.all.proxy_ndp = 1 now I have to do these ip -6 neigh add proxy homeprefix::1 dev eth0 ip -6 neigh add proxy homeprefix::### dev eth0 the question, can I do something to avoid these "ip -6 neigh ..."? if yes, what? and how? can the hoster do something? if yes, what? Thanks, Walter my ISP told me that he won't deploy IPv6 within the next 5 years; ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Upgrade OpenSSH version to the latest stable version on CentOS Linux release 7.9.2009 (Core).
On Dec 1, 2020, at 00:49, Peter wrote: > > On 1/12/20 4:04 pm, Kaushal Shriyan wrote: >> I am running CentOS Linux release 7.9.2009 (Core). Is there a way to >> upgrade OpenSSH version openssh-7.4p1-21.el7.x86_64 to the latest stable >> version openssh-server 8.4 using yum repositories or rpm binaries? > > No, 7.4p1-21 is the most recent up to date version in CentOS 7. See > https://access.redhat.com/security/updates/backporting/ for more info. Perhaps it would help to explain why you need the 8.4 release? I’d there a feature you need not in the version in C7? -- Jonathan Billings ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] CentOS and mdadm
On 12/1/20 3:48 AM, Nicolas Kovacs wrote: If anyone can explain the exact meaning of --metadata, I'd be grateful. I think the man page is pretty clear on that one. There are two different versions of the metadata block, and the second one (1.x) can be stored at different locations depending on your purpose. For example, if you want to MD RAID (mirror) your EFI System partition, you can store the metadata that identifies the partition as an MD RAID component at the end of the partition. The UEFI firmware will ignore the metadata and read the partition as if it were not a member (and that's OK as long as it's read-only). However, a partition with metadata at the end would be difficult to resize, so that's not the preferred location for most components. Oh, and is it OK to use --metadata=1.2 in CentOS 7.x and 8.x ? Yes. 2. I'm regularly encountering the mdadm --misc option in various tutorials on the Internet. I looked it up in mdadm's manpage, but it doesn't seem to be documented. Any idea what this option does ? It's one of the major modes, and assumed if no other mode is specified. See the MODES and OPTIONS sections near the beginning of the mdadm man page. I'm guessing that --misc used to be required in order to use any of the options specified in the "For Misc mode" section. ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
[CentOS-docs] [centos/centos.org] branch master updated (ad2e60b -> 997042e)
This is an automated email from the git hooks/post-receive script. rbowen pushed a change to branch master in repository centos/centos.org. from ad2e60b Removed inactive Node4 sponsor add 997042e Wow. That was really out of date. No new revisions were added by this update. Summary of changes: _includes/centos-news.html | 7 +-- 1 file changed, 5 insertions(+), 2 deletions(-) -- To stop receiving notification emails like this one, please contact the administrator of this repository. ___ CentOS-docs mailing list CentOS-docs@centos.org https://lists.centos.org/mailman/listinfo/centos-docs
[CentOS] CentOS and mdadm
Hi, I'm regularly using software RAID for my CentOS storage servers, either with RAID 1 or RAID 6 depending on the number of disks. Here's two questions about mdadm I've always been wondering about. 1. I'm not sure about the --metadata option. Let's say I want to create a simple RAID 1 setup, I'm usually doing it like this: # mdadm --create /dev/md/boot --level=1 --raid-devices=2 \ --metadata=1.2 /dev/sda1 /dev/sdb1 If anyone can explain the exact meaning of --metadata, I'd be grateful. Oh, and is it OK to use --metadata=1.2 in CentOS 7.x and 8.x ? 2. I'm regularly encountering the mdadm --misc option in various tutorials on the Internet. I looked it up in mdadm's manpage, but it doesn't seem to be documented. Any idea what this option does ? Cheers, Niki -- Microlinux - Solutions informatiques durables 7, place de l'église - 30730 Montpezat Site : https://www.microlinux.fr Blog : https://blog.microlinux.fr Mail : i...@microlinux.fr Tél. : 04 66 63 10 32 Mob. : 06 51 80 12 12 ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Physical position of swap partition on the disk
On Tue, Dec 1, 2020, 2:53 AM Roberto Ragusa wrote: > > Finally, swap throughput really matters when hibernating to disk. > > And that's really the only time it should matter on a modern system,. I rarely see /any/ swap in use for normal server or workstation operations ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Physical position of swap partition on the disk
On 11/30/20 1:55 PM, Jonathan Billings wrote: On Nov 30, 2020, at 02:35, Nicolas Kovacs wrote: * /dev/sda1: 500 MB /boot ext2 * /dev/sda2: 4 GB swap * /dev/sda3: 55 GB / ext4 I'd be curious to know what's the reason behind this, and if this kind of configuration detail is really significant. When most of us had storage on rotational storage, the fastest, lowest latency access was close to the physical center of the disc, which corresponds to the start of the disk. You’d want swap to be highly responsive in case it was used for active processes. Well, actually it is the opposite. The first blocks of the disk are on the edge of the disk and they have better throughput since the the track is longer and contains more data to be read in a single disk revolution (rpm is a constant). The idea is that you have swap at the beginning because it needs the best performance, then you have your data immediately after. Having the swap at the end is the worst choice because it is in the slowest zone and it is typically very far from a partially filled data partition at the beginning of the disk, causing a lot of head movement when swapping. The advantage in no-swapping case is minimal, because the swap partition is usually small and having your data starting at 0% of the disk space or at 3% doesn't matter a lot. Finally, swap throughput really matters when hibernating to disk. If you have both your swap and filesystems in an LVM volume, you can shuffle and rearrange them on the disk as you prefer without even a reboot (pvmove with explicit extent indications). Regards. -- Roberto Ragusamail at robertoragusa.it ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
