[CentOS] kvm CLI :: meaning of "vlan=" and "name=" options in -net nic and -net tap
Did not get any response in the CentOS Virt list. Posting in the CentOS General list hoping that some one here can provide clarification. Thx, -- Arun Khan -- Forwarded message -- From: Arun Khan Date: Tue, Jun 12, 2012 at 8:54 PM Subject: Meaning of "vlan=" and "name=" in Linux KVM To: CentOS Virt Greetings KVM gurus, I am trying to understand a "use case" scenario for the "vlan=n" option and "name=name" for the "-net nic" and "-net tap" directives. I have done some search but I have not come up with anything that sheds any light on the above. Network options: -net nic[,vlan=n][,macaddr=mac][,model=type] [,name=name][,addr=addr][,vectors=v] Create a new Network Interface Card and connect it to VLAN n (n = 0 is the default). The NIC is an e1000 by default on the PC target. Optionally, the MAC address can be changed to mac, the device address set to addr (PCI cards only), and a name can be assigned for use in monitor commands. Optionally, for PCI cards, you can specify the number v of MSI-X vectors that the card should have; this option currently only affects virtio cards; set v = 0 to disable MSI-X. If no -net option is specified, a single NIC is created. Qemu can emulate several different models of network card. Valid values for type are "virtio", "i82551", "i82557b", "i82559er", "ne2k_pci", "ne2k_isa", "pcnet", "rtl8139", "e1000", "smc91c111", "lance" and "mcf_fec". Not all devices are supported on all targets. -net tap[,vlan=n][,name=name][,fd=h][,ifname=name] [,script=file][,downscript=dfile] Connect the host TAP network interface name to VLAN n, use the network script file to configure it and the network script dfile to deconfigure it. If name is not provided, the OS automatically provides one. fd=h can be used to specify the handle of an already opened host TAP interface. The default network configure script is /etc/qemu-ifup and the default network deconfigure script is /etc/qemu-ifdown. Use script=no or downscript=no to disable script execution. My objective is to create a small "virtual" network using bridges/tap interfaces on the Host OS and running the Guest OSs (the network segment separated by vlan=somenumber) My hypothesis is that with "vlan=X" and "name=somename" the VMs can be separated into different segments i.e. a set of tap interfaces on vlan=10 and another set of tap interfaces on vlan=20 connected to the same bridge br0. I have two VMs started with "kvm -net tap,vlan=10" and "kvm -net tap,vlan=20" respectively but with IP numbers in the same subnet 172.16.0.0/24; they are able to ping each other with different "vlan" numbers. I would appreciate any clarification on the "vlan=" and "name=" options. Sample script for my KVM VMs #!/bin/bash kvm \ -vga std \ -m 1024 \ -cpu core2duo \ -smp 2,cores=2 \ -drive file=/home/kvmusr/KVM/vdisks/centos62.img,index=0 \ -net nic,vlan=1,model=e1000,macaddr=${nic_mac_addr0} \ -net tap,vlan=1,ifname=tap0,script=no,downscript=no \ Thanks, -- Arun Khan ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] space problem
On Wednesday 13 June 2012, Johnny Hughes wrote: > If it was 100% full, and if you freed up 42GB, then it would be: > > 2006/2048 = 98% full (well, 97.95% to be exact). > > so it would only show 2% space free max anyway. And by default 5% is reserved for root, so a drive can be 5% free and still say it's full to a normal user. Yves -- Yves Bellefeuille "La Esperanta Civito ne rifuzas anticipe la kunlaboron de erarintoj, se ili konscias pri sia eraro." -- Heroldo Komunikas, n-ro 473. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Best way to duplicate a live Centos 5 server?
How about using one of the backup tools to image the server? We use Symantec System Recovery and image all the disks. We then have the option of restoring to different hardware (physical or virtual) which works very well. There's a 60-day evaluation period. http://www.symantec.com/products/trialware.jsp?pcid=pcat_business_cont&pvid=1602_1 --Russell -Original Message- From: centos-boun...@centos.org [mailto:centos-boun...@centos.org] On Behalf Of Emmanuel Noobadmin Sent: Thursday, 14 June 2012 2:36 a.m. To: CentOS mailing list Subject: Re: [CentOS] Best way to duplicate a live Centos 5 server? I'm using KVM so didn't have the tool. While Les' suggestion looked like it was going to be pretty useful for a variety of backup/restore situations, I didn't know if I had the time to go through the docs and get things working in time. So in the end I went with the repeated rSync method Scott mentioned. The advantage is, I also went and made the new system C6 first, then rsync the necessary data files instead of leaving it still on C5. Thankfully nothing broke, well, except SSL certs for some reason but that was easily fixed once people started complaining. On 6/13/12, Tris Hoar wrote: > > On 08/06/2012 17:33, Emmanuel Noobadmin wrote: >> I've got a CentOS 5 server that I want to migrate over into a >> virtualized instance. >> The problem is I need to minimize downtime so was trying to figure >> out a way to "live" clone the original. >> >> Initially, I thought I could do this via exporting an iSCSI target >> from the virtual host, create a MD raid 1 array on the C5 server, >> wait for it to sync, then shutdown the physical server and switch to >> the virtual one. >> >> But after getting iSCSI working... I realize I could not create a md >> device on a mounted disk. Unfortunately this old C5 wasn't setup with >> md raid 1 originally so I can't just add a the iSCSI target as an >> additional member for a triplicate. >> >> So I remembered DRBD was supposed to be used for replication. >> >> But after getting things set up, running the drbd-admin create-md >> command gave me this scary warning it will destroy data on the disk. >> Apparently because drbd writes meta data to the drive. So that >> appears to be a no go too. >> >> Am I missing something glaringly obvious here, or is the only way I'm >> going be able to migrate is to shutdown the C5 server for a few hours >> while duping the old drives? Would greatly appreciate any pointers >> how best to do this. >> > > You don't say what virtualisation platform you are using is, but if > it's VMware, then you can use VMware converter to do the migration. > This can, if you want, clone the physical computer into VMware, shut > down the physical computer and bring up the new virtual instance. All > whilst the physical remained up. I've used it for a few Linux boxes, > where I've wanted a quick dev version of an existing server and its been fine. > > I guess, you could try pulling it into an ESXi host, and then > exporting that in a format whatever virtualisation program it is you use > supports... > > Regards, > > Tris > > * > This email and any files transmitted with it are confidential and > intended solely for the use of the individual or entity to whom they > are addressed. If you have received this email in error please notify > postmas...@bgfl.org > > The views expressed within this email are those of the individual, and > not necessarily those of the organisation > * > > ___ > CentOS mailing list > CentOS@centos.org > http://lists.centos.org/mailman/listinfo/centos > ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos === Attention: The information contained in this message and/or attachments from AgResearch Limited is intended only for the persons or entities to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipients is prohibited by AgResearch Limited. If you have received this message in error, please notify the sender immediately. === ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] space problem
Les Mikesell wrote: > On Wed, Jun 13, 2012 at 1:36 PM, wrote: >>> >> Actually, IIRC, one directory was 42G, and the other was 15G or so. >> That, along with reducing the reserved blocks on the f/s should have given me >> 3%-4%. I know that; what's driving me nuts is df, not df -h, is showing >> "available" as a blank. >> >> Oh, and for the other folks who wondered, we use rsync with hard links. > > So... are you sure the things you removed to clear space were the > _last_ hardlinks to the data? Otherwise, for the same reason you use > the links to save space, you don't get the space back. Well, I found a bit more space - of the two directories I moved, I'd forgotten to delete one (I was doing an offline backup at the time, and didn't want that to take more hours). I now see 0 available, and /dev/sdb11922858352 1892387276 0 100% /export/3 But even with that 60G + the reserved block count reduced from 24174711 to 16116474, it's still showing nothing free, and the used only shows 30G free. mark mark ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Update issue - tar package problem?
Hello Tom, On Tue, 2012-06-12 at 17:12 +0100, Tom Brown wrote: > To close the loop on this by making the 32 bit tar package available > to the system during the update allowed the update to progress as it > got pulled in as a dep during the yum run and all was happy. I suppose my idea that this might not be a multi arch issue is probably bogus. This issue might be worth reporting upstream, although I think you should report this against redhat-lsb, not tar. It might have something to do with rpm assuming the Requires: /bin/tar in the redhat-lsb spec file to be a i386 binary by default. If you look at that spec file you see that all required libraries have a conditional arch qualifier. Perhaps that is actually needed for explicitly required binaries too. Although that might still cause a catch 22 when upgrading redhat-lsb for both archs as in this case the requirement for one of the archs is still unsatisfied as only one /bin/tar is available. Anyway, probably worth reporting upstream. Regards, Leonard. -- mount -t life -o ro /dev/dna /genetic/research ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] space problem
On Wed, Jun 13, 2012 at 1:36 PM, wrote: >> > Actually, IIRC, one directory was 42G, and the other was 15G or so. That, > along with reducing the reserved blocks on the f/s should have given me > 3%-4%. I know that; what's driving me nuts is df, not df -h, is showing > "available" as a blank. > > Oh, and for the other folks who wondered, we use rsync with hard links. > So... are you sure the things you removed to clear space were the _last_ hardlinks to the data? Otherwise, for the same reason you use the links to save space, you don't get the space back. -- Les Mikesell lesmikes...@gmail.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] space problem
Johnny Hughes wrote: > On 06/13/2012 12:18 PM, m.r...@5-cent.us wrote: >> CentOS 6.2. I have a 2TB drive, one partition, which is used for online >> backups. It filled up the other day. I moved a couple of b/u directories >> off it, and deleted the originals, which should have given me 42G free. >> I also reduced the reserved blocks by 1/3rd. >> >> I've just finished an fsck, which it needed anyway, and in which there >> was a problem in an HTREE directory node. >> >> df *still* tells me that there are zero bytes free. >> >> Clues? > > A 2TB drive is 2048 GB. > If it was 100% full, and if you freed up 42GB, then it would be: > 2006/2048 = 98% full (well, 97.95% to be exact). > so it would only show 2% space free max anyway. Actually, IIRC, one directory was 42G, and the other was 15G or so. That, along with reducing the reserved blocks on the f/s should have given me 3%-4%. I know that; what's driving me nuts is df, not df -h, is showing "available" as a blank. Oh, and for the other folks who wondered, we use rsync with hard links. mark ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] space problem
On 06/13/2012 12:18 PM, m.r...@5-cent.us wrote: > CentOS 6.2. I have a 2TB drive, one partition, which is used for online > backups. It filled up the other day. I moved a couple of b/u directories > off it, and deleted the originals, which should have given me 42G free. I > also reduced the reserved blocks by 1/3rd. > > I've just finished an fsck, which it needed anyway, and in which there was > a problem in an HTREE directory node. > > df *still* tells me that there are zero bytes free. > > Clues? A 2TB drive is 2048 GB. If it was 100% full, and if you freed up 42GB, then it would be: 2006/2048 = 98% full (well, 97.95% to be exact). so it would only show 2% space free max anyway. signature.asc Description: OpenPGP digital signature ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] space problem
On 06/13/2012 12:18 PM, m.r...@5-cent.us wrote: > CentOS 6.2. I have a 2TB drive, one partition, which is used for online > backups. It filled up the other day. I moved a couple of b/u directories > off it, and deleted the originals, which should have given me 42G free. I > also reduced the reserved blocks by 1/3rd. > > I've just finished an fsck, which it needed anyway, and in which there was > a problem in an HTREE directory node. > > df *still* tells me that there are zero bytes free. > > Clues? maybe the files you removed are still open by some other process? info unlink The `unlink' function deletes the file name FILENAME. If this is a file's sole name, the file itself is also deleted. (Actually, if any process has the file open when this happens, deletion is postponed until all processes have closed the file.) use lsof to find processes which might still have the file open. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] space problem
On 2012-06-13, m.r...@5-cent.us wrote: > CentOS 6.2. I have a 2TB drive, one partition, which is used for online > backups. It filled up the other day. I moved a couple of b/u directories > off it, and deleted the originals, which should have given me 42G free. I > also reduced the reserved blocks by 1/3rd. How are you taking backups? If you're using something like rsnapshot, you may have only deleted one of the many hard links to your files. In doing so you may have removed the directory entries but your files are still there. (That should still have freed up some space, just not much.) Also, perhaps check df -i? --keith -- kkel...@wombat.san-francisco.ca.us ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] space problem
CentOS 6.2. I have a 2TB drive, one partition, which is used for online backups. It filled up the other day. I moved a couple of b/u directories off it, and deleted the originals, which should have given me 42G free. I also reduced the reserved blocks by 1/3rd. I've just finished an fsck, which it needed anyway, and in which there was a problem in an HTREE directory node. df *still* tells me that there are zero bytes free. Clues? mark ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] set perms on ttyUSB
On 06/13/2012 12:29 PM, James Pearson wrote: > Steve Clark wrote: >> Hello, >> >> CentOS 6.2. >> >> I have spent all morning googling and trying different things to get the >> permissions >> on my ttyUSB0 port set correctly using udev. I am at my wits end. Why is >> this so convoluted!? >> >> I would really appreciate it if someone could tell me how to do this. >> >> The default permissions come up 660 root,dialout. I have tried adding myself >> to group dialout but still get permission denied when I run minicom. The only >> thing that works is sudo -i then chmod 666 /dev/ttyUSB0. > I have a /etc/udev/rules.d/99-local.rules which contains: > > KERNEL=="tty[A-Z]*",GROUP="dialout", MODE="0666" > > James Pearson > Thanks James, That did the trick - I had a similar rule but had munged it in copying it from my browser. -- Stephen Clark *NetWolves* Director of Technology Phone: 813-579-3200 Fax: 813-882-0209 Email: steve.cl...@netwolves.com http://www.netwolves.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] set perms on ttyUSB
Steve Clark wrote: > Hello, > > CentOS 6.2. > > I have spent all morning googling and trying different things to get the > permissions > on my ttyUSB0 port set correctly using udev. I am at my wits end. Why is this > so convoluted!? > > I would really appreciate it if someone could tell me how to do this. > > The default permissions come up 660 root,dialout. I have tried adding myself > to group dialout but still get permission denied when I run minicom. The only > thing that works is sudo -i then chmod 666 /dev/ttyUSB0. I have a /etc/udev/rules.d/99-local.rules which contains: KERNEL=="tty[A-Z]*",GROUP="dialout", MODE="0666" James Pearson ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] set perms on ttyUSB
Hello, CentOS 6.2. I have spent all morning googling and trying different things to get the permissions on my ttyUSB0 port set correctly using udev. I am at my wits end. Why is this so convoluted!? I would really appreciate it if someone could tell me how to do this. The default permissions come up 660 root,dialout. I have tried adding myself to group dialout but still get permission denied when I run minicom. The only thing that works is sudo -i then chmod 666 /dev/ttyUSB0. Thanks in advance. -- Stephen Clark *NetWolves* Director of Technology Phone: 813-579-3200 Fax: 813-882-0209 Email: steve.cl...@netwolves.com http://www.netwolves.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] CentOS-announce Digest, Vol 88, Issue 8
Send CentOS-announce mailing list submissions to centos-annou...@centos.org To subscribe or unsubscribe via the World Wide Web, visit http://lists.centos.org/mailman/listinfo/centos-announce or, via email, send a message with subject or body 'help' to centos-announce-requ...@centos.org You can reach the person managing the list at centos-announce-ow...@centos.org When replying, please edit your Subject line so it is more specific than "Re: Contents of CentOS-announce digest..." Today's Topics: 1. CESA-2012:0721 Important CentOS 5 kernel Update (Johnny Hughes) 2. CEBA-2012:0726 CentOS 5 rp-pppoe FASTTRACK Update (Johnny Hughes) 3. CEBA-2012:0728 CentOS 6 lldpad Update (Johnny Hughes) 4. CEBA-2012:0727 CentOS 6 libvirt Update (Johnny Hughes) -- Message: 1 Date: Wed, 13 Jun 2012 00:11:19 + From: Johnny Hughes Subject: [CentOS-announce] CESA-2012:0721 Important CentOS 5 kernel Update To: centos-annou...@centos.org Message-ID: <20120613001119.ga12...@chakra.karan.org> Content-Type: text/plain; charset=us-ascii CentOS Errata and Security Advisory 2012:0721 Important Upstream details at : https://rhn.redhat.com/errata/RHSA-2012-0721.html The following updated files have been uploaded and are currently syncing to the mirrors: ( sha256sum Filename ) i386: cbb4a31da293e11c165753949275e557ed989f83ed5bd9ff1bdd5da31d80c636 kernel-2.6.18-308.8.2.el5.i686.rpm ea33676e3b72e3d74bc67538abf4eb261f43236ff5624fe8f95d8743d7eae448 kernel-debug-2.6.18-308.8.2.el5.i686.rpm 88b655d8310f7dcb5db276de5755d67c7538798aa2fcdf13a44a8625471f0c1f kernel-debug-devel-2.6.18-308.8.2.el5.i686.rpm 4ea808bd8ca6a90bf6f8c9d0ba6a2cb9ff24cda84c0729ba6f1b11a2663d10f4 kernel-devel-2.6.18-308.8.2.el5.i686.rpm 409ea419465826ecc3e8f5ca226fc862cc4b058adb725c84e9c4c68390f8c8de kernel-doc-2.6.18-308.8.2.el5.noarch.rpm 9052b183ff52d80f67a7b52663f761cc9d6cfd1db480ba6ed5b38f15982a6e23 kernel-headers-2.6.18-308.8.2.el5.i386.rpm 0b04d3a84ce29460b545f03102422dfbfa5e0d6f5c320f0c86ad83be513b81f3 kernel-PAE-2.6.18-308.8.2.el5.i686.rpm ed3b3cb0f95ad5217c04d5e0cb53975ebd87b0bd0971b169f41ae3f4313578ea kernel-PAE-devel-2.6.18-308.8.2.el5.i686.rpm e2d5facb99b47f353e485bdac3dd270d1e4b2b1a13407d00161b5fb9d41566bc kernel-xen-2.6.18-308.8.2.el5.i686.rpm 14a82f4c262215b67d7c7c6d22c0fa32ba65ade61b80c728c166b43ddc00b26f kernel-xen-devel-2.6.18-308.8.2.el5.i686.rpm x86_64: d936dd354fd9fbb409ddf415ad7ea87d3b9870e419e58e7925a50d0cc3889713 kernel-2.6.18-308.8.2.el5.x86_64.rpm da112881ff2dd48d45349d0997ebc0cdfe53dcaa078c6f34055c488a61222452 kernel-debug-2.6.18-308.8.2.el5.x86_64.rpm 4e3d65f7dab2055f0fc732f4192a1d0e4e41abff7e75f1afc85c24cb24ebd0e4 kernel-debug-devel-2.6.18-308.8.2.el5.x86_64.rpm 1086c971fc75d89bfd0fcbda8e31cd807a922324e97697bc7adfe6928db068cd kernel-devel-2.6.18-308.8.2.el5.x86_64.rpm 409ea419465826ecc3e8f5ca226fc862cc4b058adb725c84e9c4c68390f8c8de kernel-doc-2.6.18-308.8.2.el5.noarch.rpm 408dd016c3f0d2efce0b27ea4b7a77505313d70bf9089528058f3e20576e4a89 kernel-headers-2.6.18-308.8.2.el5.x86_64.rpm a2073516d8ac0ebceae4668bd4036a3dad6ea743210794a3bed4678b1a07d6a2 kernel-xen-2.6.18-308.8.2.el5.x86_64.rpm a1b45d66a1bf5ede91d5ba6e09adfac4238db01cee71267c2dc5f55d27d78452 kernel-xen-devel-2.6.18-308.8.2.el5.x86_64.rpm Source: e0fb314918e345984377ba34aa77aaf1dc5420c1e203e721c16068c8af94b817 kernel-2.6.18-308.8.2.el5.src.rpm -- Johnny Hughes CentOS Project { http://www.centos.org/ } irc: hughesjr, #cen...@irc.freenode.net -- Message: 2 Date: Wed, 13 Jun 2012 10:32:10 + From: Johnny Hughes Subject: [CentOS-announce] CEBA-2012:0726 CentOS 5 rp-pppoe FASTTRACK Update To: centos-annou...@centos.org Message-ID: <20120613103210.ga10...@chakra.karan.org> Content-Type: text/plain; charset=us-ascii CentOS Errata and Bugfix Advisory 2012:0726 Upstream details at : http://rhn.redhat.com/errata/RHBA-2012-0726.html The following updated files have been uploaded and are currently syncing to the mirrors: ( sha256sum Filename ) i386: 94e78d77c3dbd7ec9d26ba22e2f3bf4d7952721088cdc6a1999ec274f387cb20 rp-pppoe-3.5-33.el5.i386.rpm x86_64: 53330ac8981cae9f1c865748c15fbbf4b0ef4b5bc1dca67114b78e504bbc6230 rp-pppoe-3.5-33.el5.x86_64.rpm Source: 39e1deac26fe937f15b11b39314aea99e699c7baea92775ff38151ea4053d0e2 rp-pppoe-3.5-33.el5.src.rpm -- Johnny Hughes CentOS Project { http://www.centos.org/ } irc: hughesjr, #cen...@irc.freenode.net -- Message: 3 Date: Wed, 13 Jun 2012 11:41:40 + From: Johnny Hughes Subject: [CentOS-announce] CEBA-2012:0728 CentOS 6 lldpad Update To: centos-annou...@centos.org Message-ID: <20120613114140.ga14...@chakra.karan.org> Content-Type: text/plain; charset=us-ascii CentOS Errata and Bugfix Advisory 2012:0728 Upstream details at : https://rhn.redhat.com/errata/RHBA-2012-0728.html The follow
Re: [CentOS] Centos 6 - Networking: Some Queries -- GURUS HELP PL
On Wed, Jun 13, 2012 at 1:52 AM, Sanjay Arora wrote: > >> It might be easier to suggest an approach if you describe what you >> need to do. You can't magically make new public addresses that aren't >> available appear on an existing network, whether it is on real or >> virtual NICs. But there are ways to tunnel access to different >> private networks to each other or to reverse-proxy connections to a >> public address to a server on a private address. >> > > My machine is on LAN 192.168.1.0/24, has an IP of 192.168.1.3. This > Network has GW 192.168.1.1 which is an adsl router in the office. No > firewall on the router. Other LAN machines have IPs in the > 192.168.1.0/24 network & I'm not allowed to use those IPs. They are > reserved for LAN use. OK, I don't quite understand what 'reserved for LAN' use means. I'll assume it means someone else controls it and they won't cooperate if you bridge you VM's to the LAN. In most scenarios, the adsl router would give out DHCP addresses and unless you run out, bridged machines would just grab their own address and work just like a new physical machine. > Now My machine has a second card for LTSP Network (it is a LTSP > Server) with IP 172.16.1.0/24 > > I want Virtual hosts on my machine so I have to have a different IP > rangesay 192.168.2.0/24 > > And I want routing among three as well as Internet access through the > NATTED adsl router which has a dynamic IP. > > This is my problem. You still don't say what kind of access you need - or why you can't bridge on the 172.16.1.0 side which eliminates half of the problem. Outbound connections are easy - your LTSP clients probably already have that via NAT on the server, and they also should be using the server as their default gateway. If you don't want the VM guests on the same subnet, you can create a new guest-only subnet with the same setup as the LTSP side (server is default gateway and can route among all networks). So you only have a problem if you need to accept inbound connections from the LAN or internet. You probably don't have that now for the LTSP subnet. Do you need it for the VMs? -- Les Mikesell lesmikes...@gmail.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Best way to duplicate a live Centos 5 server?
I'm using KVM so didn't have the tool. While Les' suggestion looked like it was going to be pretty useful for a variety of backup/restore situations, I didn't know if I had the time to go through the docs and get things working in time. So in the end I went with the repeated rSync method Scott mentioned. The advantage is, I also went and made the new system C6 first, then rsync the necessary data files instead of leaving it still on C5. Thankfully nothing broke, well, except SSL certs for some reason but that was easily fixed once people started complaining. On 6/13/12, Tris Hoar wrote: > > On 08/06/2012 17:33, Emmanuel Noobadmin wrote: >> I've got a CentOS 5 server that I want to migrate over into a >> virtualized instance. >> The problem is I need to minimize downtime so was trying to figure out >> a way to "live" clone the original. >> >> Initially, I thought I could do this via exporting an iSCSI target >> from the virtual host, create a MD raid 1 array on the C5 server, wait >> for it to sync, then shutdown the physical server and switch to the >> virtual one. >> >> But after getting iSCSI working... I realize I could not create a md >> device on a mounted disk. Unfortunately this old C5 wasn't setup with >> md raid 1 originally so I can't just add a the iSCSI target as an >> additional member for a triplicate. >> >> So I remembered DRBD was supposed to be used for replication. >> >> But after getting things set up, running the drbd-admin create-md >> command gave me this scary warning it will destroy data on the disk. >> Apparently because drbd writes meta data to the drive. So that appears >> to be a no go too. >> >> Am I missing something glaringly obvious here, or is the only way I'm >> going be able to migrate is to shutdown the C5 server for a few hours >> while duping the old drives? Would greatly appreciate any pointers how >> best to do this. >> > > You don't say what virtualisation platform you are using is, but if it's > VMware, then you can use VMware converter to do the migration. This can, > if you want, clone the physical computer into VMware, shut down the > physical computer and bring up the new virtual instance. All whilst the > physical remained up. I've used it for a few Linux boxes, where I've > wanted a quick dev version of an existing server and its been fine. > > I guess, you could try pulling it into an ESXi host, and then exporting > that in a format whatever virtualisation program it is you use supports... > > Regards, > > Tris > > * > This email and any files transmitted with it are confidential > and intended solely for the use of the individual or entity > to whom they are addressed. If you have received this email > in error please notify postmas...@bgfl.org > > The views expressed within this email are those of the > individual, and not necessarily those of the organisation > * > > ___ > CentOS mailing list > CentOS@centos.org > http://lists.centos.org/mailman/listinfo/centos > ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] unfsd scalability issues
Boris Epstein wrote: > On Sat, Jun 2, 2012 at 2:50 PM, John R. Dennison wrote: >> On Sat, Jun 02, 2012 at 10:59:13AM -0400, Boris Epstein wrote: > To be specific, I use UNFSD to export a MooseFS file system. MooseFS, by > the way, is userland-process based too. > > Be that as it may, I've seen situations where a comparably configured > MooseFS client get to read at, say, 40 MB/s - which is fine - but the > UNFSD at the same time reads at 40K/s(!) Why would that be? I mean, some > degradation I can dig but 3 orders of magnitude? What is with this? Am I > doing something wrong? I wonder... what's the architecture of what you're getting these results? I tried opening a bug with upstream over NFS4 and 6.x, and no one ever looked at it, and they closed it. 100% repeatably: unpack a package locally, seconds. unpack it from an NFS mount onto a local drive, about 1 min. unpack it from an NFS mount onto an NFS mount, even when the target is exported FROM THE SAME MACHINE* that the process is running on: 6.5 - 7 MINUTES. * That is, [server 1] [server 2] /export/thatdir --NFS-->/target/dir /s2/source /source/dir --NFS-->/s2/source and cd [server 2]:/target/dir and unpack from /s2/source I suppose I'll try logging into upstream's bugzilla using our official licensed id; maybe then they'll assign someone to look at it mark ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] unfsd scalability issues
On Sat, Jun 2, 2012 at 2:50 PM, John R. Dennison wrote: > On Sat, Jun 02, 2012 at 10:59:13AM -0400, Boris Epstein wrote: > > > > A process implemented in the userland may not be as efficient as one > > implemented as part of the kernel - but that doesn't mean it can't scale > > well, does it? > > Depends on ones definition of scale I suppose. I consider efficiency > and performance one factor of scaling. To be completely honest about > this I must admit that I've not spent a lot of time benchmarking any > user space implementation in a large deployment but I wouldn't expect > performance to ramp up based on scale. > > I've always had a strong aversion to file systems implemented in > user space versus kernel space as I've (personally) never found such an > implementation that had what I considered good performance. > > My needs, however, are not yours. If your requirements give you leeway > for higher latency and slower overall performance perhaps a userland > file system will work perfectly fine for you. As with all else in the > IT sector use what works best for you :) > > > > > >John > -- > Human beings hardly ever learn from the experience of others. They learn; > when they do, which isn't often, on their own, the hard way. > > -- Robert Heinlein (1907-1988), American science fiction writer, Time > Enough for Love (1973) > > > > John, To be specific, I use UNFSD to export a MooseFS file system. MooseFS, by the way, is userland-process based too. Be that as it may, I've seen situations where a comparably configured MooseFS client get to read at, say, 40 MB/s - which is fine - but the UNFSD at the same time reads at 40K/s(!) Why would that be? I mean, some degradation I can dig but 3 orders of magnitude? What is with this? Am I doing something wrong? I can't believe it works the same way for everybody - who would use it if it did? Boris. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] yum install, and exit status
Hello, IIRC, the exit status of "yum install foo bar" was (long ago !) 0 only if foo *and* bar could be installed. Nowadays, it is 0 if foo *or* bar (or both) are correctly installed. Is there a way to get the old behavior ? Thanks, -- Philippe Naudin ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] Help with smartd
I have a system that is logging: smartd /dev/sda currently unreadble (pending) sectors smartd /dev/sda offline uncorrectable sectors The box continues to run fine. Doing "smartctl -H /dev/sda" says: test result: PASSED I have ran the "smartctl -t offline /dev/sda", after the 300+ seconds I rebooted and waited about 30 minutes and again got the above error, and smartctl -H says PASSED. How do I tell smartctl to just not use the sectors its finding bad and move on? Thanks, Jerry ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Best way to duplicate a live Centos 5 server?
On 08/06/2012 17:33, Emmanuel Noobadmin wrote: > I've got a CentOS 5 server that I want to migrate over into a > virtualized instance. > The problem is I need to minimize downtime so was trying to figure out > a way to "live" clone the original. > > Initially, I thought I could do this via exporting an iSCSI target > from the virtual host, create a MD raid 1 array on the C5 server, wait > for it to sync, then shutdown the physical server and switch to the > virtual one. > > But after getting iSCSI working... I realize I could not create a md > device on a mounted disk. Unfortunately this old C5 wasn't setup with > md raid 1 originally so I can't just add a the iSCSI target as an > additional member for a triplicate. > > So I remembered DRBD was supposed to be used for replication. > > But after getting things set up, running the drbd-admin create-md > command gave me this scary warning it will destroy data on the disk. > Apparently because drbd writes meta data to the drive. So that appears > to be a no go too. > > Am I missing something glaringly obvious here, or is the only way I'm > going be able to migrate is to shutdown the C5 server for a few hours > while duping the old drives? Would greatly appreciate any pointers how > best to do this. > You don't say what virtualisation platform you are using is, but if it's VMware, then you can use VMware converter to do the migration. This can, if you want, clone the physical computer into VMware, shut down the physical computer and bring up the new virtual instance. All whilst the physical remained up. I've used it for a few Linux boxes, where I've wanted a quick dev version of an existing server and its been fine. I guess, you could try pulling it into an ESXi host, and then exporting that in a format whatever virtualisation program it is you use supports... Regards, Tris * This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify postmas...@bgfl.org The views expressed within this email are those of the individual, and not necessarily those of the organisation * ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] php4 under Centos6
On 12/06/2012 21:45, Michael Kress wrote: > Am 12.06.2012 22:39, schrieb Reindl Harald: >> Am 12.06.2012 22:19, schrieb Michael Kress: >>> Hello, is there any way of getting php4 installed on Centos6? I'd like >>> to install it in an apache/fastcgi environment. >>> Has anybody got a link to a description/howto describing a clean install? >>> I failed compiling the original php4 tar ball and failed relocating the >>> php binary. >> PHP4 IS DEAD SINCE A LONG TIME >> >> DO NOT USE PHP4 - THROW AWAY CRAP WHICH DOES NOT >> WORK WITH PHP5 BECAUSE IT IS UNMAINTAINED AND >> UNSECURE >> > > > oh yes, forgot the disclaimer with the above text. > Regards > Michael > I'm assuming that this would only be for a very specific issue that you have, and not externally facing. If so and I had to use something this old, I'd just use CentOS 3 http://vault.centos.org/3.9/ That came with php-4.3.2. the dep list that you would need to resolve to make the RPM work correctly on CentOS 6 is quite long. Regards, Tris * This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify postmas...@bgfl.org The views expressed within this email are those of the individual, and not necessarily those of the organisation * ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - Networking: Some Queries -- GURUS HELP PL
On 06/12/12 11:52 PM, Sanjay Arora wrote: > And I want routing among three as well as Internet access through thet > NATTED adsl router which has a dynamic IP. for that sort of routing to work, all the other hosts on hte 2 LANs will need to know the route to that subnet is via the NIC interfaces of the host.. this can be done via RIP or another route announcement protocol, or it can be done by statically configuring the routes on each host. the internet router will need to know that route too. -- john r pierceN 37, W 122 santa cruz ca mid-left coast ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos