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Re: [CentOS] security cameras
by Chuck Munro 25 Feb '11

25 Feb '11

On 02/24/2011 09:00 AM, centos-request(a)centos.org wrote: > On 02/23/2011 01:36 PM John R Pierce wrote: >> > On 02/23/11 10:16 AM, Keith Roberts wrote: >>> >> I think you will get far better video quality using CCTV >>> >> cameras than a webcam on a USB port. >> > >> > you may think that, but those solutions you mentioned are all NTSC >> > composite video, while even a $30 USB webcam now days is 2 megapixels or >> > higher. >> > >> > anyways, the OP wants cameras that connect to the network and get their >> > power off the ethernet cable, not a USB or a CCTV camera. >> > .... > Yes. True. I'm not interested in either USB or CCTV. Ethernet cams > are much better and smarter technology and, from what I hear, easier to > install and set up. From experience I can attest to the fact that PAL/NTSC CCTV cameras are significantly inferior to modern digital security cameras. I have used devices from Axis, who appear to be the largest and most diverse manufacturer (www.axis.com) but they're not the cheapest. As an aside, Axis cameras run embedded Linux. The newer Ethernet-enabled cameras can use POE (power over Ethernet) but you'll need either a power supply that you insert somewhere along the cable run, or a POE-enabled switch which supplies power to its Ethernet ports. Several brands are available. Using POE makes a lot of sense and saves a lot of trouble, but make sure your Ethernet cable installation is of high quality. Open-source software such as ZoneMinder works with cameras from several manufacturers, and runs on CentOS. I personally haven't tried it, but I understand it works well. Chuck

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Detecting harddrive problem
by Fajar Priyanto 25 Feb '11

25 Feb '11

Hi all, Recently I realize the filesystem became Read-only and there is "media error" message in the system log. It has passed several days without notice. I'm thinking of setting up a script to grep that "media error" and send email. Is there more elegant way of doing this? Thank you.

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wicd questions
by lostson 25 Feb '11

25 Feb '11

Hello I am trying to get wicd to work on Cent 5.5 it installs fine but when i run wicd-curses i get this error wicd-curses File "/usr/share/wicd/curses/wicd-curses.py", line 505 class appGUI(): ^ SyntaxError: invalid syntax my versions of wicd and python-urwid are wicd-1.7.0-3.el5 python-urwid-0.9.8.4-3.el5 Has anyone been able to get wicd working ? Or does anyone know how to fix the python syntax error ? I would like to be able to control my wireless networks via command line. btw this is not a centos base package so flame away please & thanks. LostSon CentOS - It's not just for servers ya know...

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Re: [CentOS] how to optimize CentOS XEN dom0?
by Ross Walker 25 Feb '11

25 Feb '11

On Feb 25, 2011, at 9:28 AM, Rudi Ahlers <Rudi(a)SoftDux.com> wrote: > On Fri, Feb 25, 2011 at 4:21 PM, Ross Walker <rswwalker(a)gmail.com> wrote: > > >> >> It seems dom0's memory got under pressure from the other domUs. >> >> Make sure to set an absolute minimum of memory for dom0 in xend.conf or using the boot option (forgot what it is). I always made it to the OS min of 256MB, but if you are doing more in dom0 you'd want more. >> >> On a side, I might run all management apps in a VM and manage dom0 from that domU. >> >> >> -Ross >> >> _______________________________________________ > > > I already set dom0 to 512MB, but it seems it might not be enough. I > was hoping I could optimize it a bit more though Try setting the max as well, then it's memory allocation is fixed, say 512/512. Then the only memory pressure is between apps in dom0. -Ross

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security cameras
by ken 25 Feb '11

25 Feb '11

I heard about some inexpensive security cameras which get their power through the same cat5 cable which delivers the data/pictures (which would simplify wiring tremendously). Does anyone know about these? Do they work with Linux, particularly CentOS? tnx 4 tips.

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Re: [CentOS] how to optimize CentOS XEN dom0?
by Ross Walker 25 Feb '11

25 Feb '11

On Feb 25, 2011, at 4:29 AM, Rudi Ahlers <Rudi(a)SoftDux.com> wrote: > On Wed, Feb 23, 2011 at 4:33 PM, Ross Walker <rswwalker(a)gmail.com> wrote: >> On Feb 23, 2011, at 3:42 AM, Rudi Ahlers <Rudi(a)SoftDux.com> wrote: >> >>> On Wed, Feb 23, 2011 at 9:06 AM, yonatan pingle >>> <yonatan.pingle(a)gmail.com> wrote: >>>> you should have a look at your I/O disk status. >>>> >>>> try with iostat -dx 5 to see the disk utilization info over time. >>>> when it comes to slowdown on a virtual environment on a Desktop grade >>>> machine, i suspect disk I/O latency and bottleneck as a cause. >>> >>> Thanx, I don't know how to interpret the results (yet), but here's the >>> current output: >>> >>> Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz >>> avgqu-sz await svctm %util >> >> Knowing the columns helps here, >> >> rrqm/s and wrqm/s, mean read/write requests merged a second, shows how well scheduler is merging contiguous io operations >> >> r/s and w/s, read/write io operations a second >> >> rsec/s and wsec/s, read/write sectors a second, I usually use the -k option so it displays as kilobytes a second >> >> avgrq-sz, shows average request size in the unit of choice, here being sectors, I wish it'd separate reads from writes, but oh well >> >> avgqu-sz, average amount of io operations waiting for service, smaller is better >> >> await, average time an io operation waited on queue to be serviced in ms, again smaller is better >> >> svctm, last time it took to service an io operation, how long the drive took to perform the operation from when it left queue to when a result was returned >> >> %util, the estimated drive utilization based on svctm, await and avgqu-sz >> >> For lockups though I'd look at dmesg and xen log, xmlog I think is the command. >> >> The number one reason for lockups though is most likely memory contention between domUs and dom0. >> >> What are you running in dom0? What are your memory reservations like? >> >> > I see a lot of these errors in /var/log/messages shortly before it crashed: > > > > Feb 22 15:27:14 zaxen01 kernel: HighMem: empty > Feb 22 15:27:14 zaxen01 kernel: 918 pagecache pages > Feb 22 15:27:14 zaxen01 kernel: Swap cache: add 2248198, delete > 2248009, find 160685591/160898897, race 0+453 > Feb 22 15:27:14 zaxen01 kernel: Free swap = 0kB > Feb 22 15:27:14 zaxen01 kernel: Total swap = 4194296kB > Feb 22 15:27:14 zaxen01 kernel: Free swap: 0kB > Feb 22 15:27:14 zaxen01 kernel: 133120 pages of RAM > Feb 22 15:27:14 zaxen01 kernel: 22818 reserved pages > Feb 22 15:27:16 zaxen01 kernel: 105840 pages shared > Feb 22 15:27:16 zaxen01 kernel: 189 pages swap cached > Feb 22 15:27:17 zaxen01 kernel: Out of memory: Killed process 17464, > UID 99, (sendmail). > Feb 23 00:35:38 zaxen01 syslogd 1.4.1: restart. > Feb 23 00:35:38 zaxen01 kernel: klogd 1.4.1, log source = /proc/kmsg started. > Feb 23 00:35:38 zaxen01 kernel: Bootdata ok (command line is ro > root=/dev/System/root rhgb quiet xencons=tty6) > Feb 23 00:35:38 zaxen01 kernel: Linux version 2.6.18-194.32.1.el5xen > (mockbuild(a)builder10.centos.org) (gcc version 4.1.2 20080704 (Red Hat > 4.1.2-48)) #1 SMP > Wed Jan 5 18:44:24 EST 2011 > Feb 23 00:35:38 zaxen01 kernel: BIOS-provided physical RAM map: > Feb 23 00:35:38 zaxen01 kernel: Xen: 0000000000000000 - > 0000000020800000 (usable) > Feb 23 00:35:38 zaxen01 kernel: DMI 2.4 present. > Feb 23 00:35:38 zaxen01 kernel: ACPI: LAPIC (acpi_id[0x01] > lapic_id[0x00] enabled) > Feb 23 00:35:38 zaxen01 kernel: ACPI: LAPIC (acpi_id[0x03] > lapic_id[0x02] enabled) > Feb 23 00:35:38 zaxen01 kernel: ACPI: LAPIC (acpi_id[0x02] > lapic_id[0x01] enabled) > Feb 23 00:35:38 zaxen01 kernel: ACPI: LAPIC (acpi_id[0x04] > lapic_id[0x03] enabled) > Feb 23 00:35:38 zaxen01 kernel: ACPI: LAPIC_NMI (acpi_id[0x01] dfl dfl > lint[0x1]) > Feb 23 00:35:38 zaxen01 kernel: ACPI: LAPIC_NMI (acpi_id[0x02] dfl dfl > lint[0x1]) > Feb 23 00:35:38 zaxen01 kernel: ACPI: IOAPIC (id[0x02] > address[0xfec00000] gsi_base[0]) > Feb 23 00:35:38 zaxen01 kernel: IOAPIC[0]: apic_id 2, version 32, > address 0xfec00000, GSI 0-23 > Feb 23 00:35:38 zaxen01 kernel: ACPI: INT_SRC_OVR (bus 0 bus_irq 0 > global_irq 2 dfl dfl) > Feb 23 00:35:38 zaxen01 kernel: ACPI: INT_SRC_OVR (bus 0 bus_irq 9 > global_irq 9 high level) > Feb 23 00:35:38 zaxen01 kernel: Setting APIC routing to xen > Feb 23 00:35:38 zaxen01 kernel: Using ACPI (MADT) for SMP > configuration information > Feb 23 00:35:38 zaxen01 kernel: Allocating PCI resources starting at > d4000000 (gap: d0000000:2ff00000) > Feb 23 00:35:38 zaxen01 kernel: Built 1 zonelists. Total pages: 133120 > Feb 23 00:35:38 zaxen01 kernel: Kernel command line: ro > root=/dev/System/root rhgb quiet xencons=tty6 > Feb 23 00:35:38 zaxen01 kernel: Initializing CPU#0 > Feb 23 00:35:38 zaxen01 kernel: PID hash table entries: 4096 (order: > 12, 32768 bytes) It seems dom0's memory got under pressure from the other domUs. Make sure to set an absolute minimum of memory for dom0 in xend.conf or using the boot option (forgot what it is). I always made it to the OS min of 256MB, but if you are doing more in dom0 you'd want more. On a side, I might run all management apps in a VM and manage dom0 from that domU. -Ross

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current bind version
by Machin, Greg 25 Feb '11

25 Feb '11

Hi. I have had an enquiry from the Network and Security guy. He wants to know why CentOS 5.5 /RHEL 5 is using a very old version of bind "bind-chroot-9.3.6-4.P1.el5_5.3" when the latest release that has many security fixes is on 9.7.3 . I understand that its to maintain a known stable platform by in introducing new elements etc .. Is there an official explanation / document that I can direct him to. Thanks Greg Machin Systems Administrator - Linux Infrastructure Group, Information Services

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CUPS / printer problems
by Timothy Kesten 25 Feb '11

25 Feb '11

Hi Folks, CentOS 5. I've installed a new printer - HP LaserJet Pro M1132 MFP Cups recognized it as HP LaserJet 3020 3030 Postscript URI: usb://HP/LaserJet%20Professional%20M1132%20MFP I try to print a testpage: No error message appears in access.log localhost - - ......................... Get-Jobs successfull-ok nor in error.log Completed successfully But also no printed page appears. What goes wrong. BTW: How can I install a new hplib (3.10) . Found some rpms but installation results in dependencies errors Thx for any hints Timothy

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[OT] building src rpm on RHEL5 using mock https://bugzilla.redhat.com/show_bug.cgi?id=680144
by Jason Pyeron 25 Feb '11

25 Feb '11

Does anyone have experience using mock on RHEL5 with the RHN? I use mock easily on Centos, I get errors like /bin/sh not found, useradd not found build failed? messages from it on RHEL w/ RHN. Any suggestions on where to start looking. -Jason Pyeron -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- - - - Jason Pyeron PD Inc. http://www.pdinc.us - - Principal Consultant 10 West 24th Street #100 - - +1 (443) 269-1555 x333 Baltimore, Maryland 21218 - - - -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- This message is copyright PD Inc, subject to license 20080407P00.

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how to optimize CentOS XEN dom0?
by Rudi Ahlers 25 Feb '11

25 Feb '11

Hi, I have a problematic CentOS XEN server and hope someone could point me in the right direction to optimize it a bit. The server runs on a Core2Quad 9300, with 8GB RAM (max motherboard can take, 1U chassis) on an Intel motherboard with a 1TB SATA HDD. dom0 is set to 512MB limit with a few small XEM VM's running: root@zaxen01:[~]$ xm list Name ID Mem(MiB) VCPUs State Time(s) Domain-0 0 512 4 r----- 96.5 actionco.vm 3 1519 1 -b---- 14.8 byracers.vm 4 511 1 -b---- 85.7 ns1 5 511 1 -b---- 22.3 picturestravel 6 255 1 -b---- 13.3 rafttheworld 7 255 1 -b---- 11.3 zafepres.vm 8 511 1 -b---- 19.0 the server itself seems to eat up a lot of resources: root@zaxen01:[~]$ free -m total used free shared buffers cached Mem: 512 472 39 0 13 215 -/+ buffers/cache: 244 268 Swap: 4095 0 4095[/CODE] Yet, it only has XEN, Webmin (since it's a CloudMin XEN server), Exim, Apache and a few other services running: root@zaxen01:[~]$ chkconfig --list |grep "3:on" |awk '{print $1}' |sort acpid auditd crond csf dhcpd exim haldaemon httpd iptables iscsi iscsid kudzu lfd lvm2-monitor mdmonitor network qemu restorecond setroubleshoot smartd snmpd sshd syslog sysstat webmin xend xendomains Is there anything I can optimize on such a server? The server runs CentOS 5.5 x64: root@zaxen01:[~]$ cat /etc/redhat-release CentOS release 5.5 (Final) root@zaxen01:[~]$ uname -a Linux zaxen01.softdux.com 2.6.18-194.32.1.el5xen #1 SMP Wed Jan 5 18:44:24 EST 2011 x86_64 x86_64 x86_64 GNU/Linux with Xen version 3.1.2-194.32.1.el5 And there's the xm dmesg output: Xen version 3.1.2-194.32.1.el5 (mockbuild(a)centos.org) (gcc version 4.1.2 20080704 (Red Hat 4.1.2-48)) Wed Jan 5 17:43:03 EST 2011 Latest ChangeSet: unavailable (XEN) Command line: dom0_mem=512M (XEN) Video information: (XEN) VGA is text mode 80x25, font 8x16 (XEN) VBE/DDC methods: V2; EDID transfer time: 1 seconds (XEN) Disc information: (XEN) Found 1 MBR signatures (XEN) Found 1 EDD information structures (XEN) Xen-e820 RAM map: (XEN) 0000000000000000 - 000000000008f000 (usable) (XEN) 000000000008f000 - 00000000000a0000 (reserved) (XEN) 00000000000e0000 - 0000000000100000 (reserved) (XEN) 0000000000100000 - 00000000cf53f000 (usable) (XEN) 00000000cf53f000 - 00000000cf54b000 (reserved) (XEN) 00000000cf54b000 - 00000000cf620000 (usable) (XEN) 00000000cf620000 - 00000000cf6e8000 (ACPI NVS) (XEN) 00000000cf6e8000 - 00000000cf6ec000 (usable) (XEN) 00000000cf6ec000 - 00000000cf6f1000 (ACPI data) (XEN) 00000000cf6f1000 - 00000000cf6f2000 (usable) (XEN) 00000000cf6f2000 - 00000000cf6ff000 (ACPI data) (XEN) 00000000cf6ff000 - 00000000cf700000 (usable) (XEN) 00000000cf700000 - 00000000d0000000 (reserved) (XEN) 00000000fff00000 - 0000000100000000 (reserved) (XEN) 0000000100000000 - 0000000230000000 (usable) (XEN) System RAM: 8181MB (8378020kB) (XEN) Xen heap: 13MB (13720kB) (XEN) Domain heap initialised: DMA width 32 bits (XEN) Processor #0 7:7 APIC version 20 (XEN) Processor #2 7:7 APIC version 20 (XEN) Processor #1 7:7 APIC version 20 (XEN) Processor #3 7:7 APIC version 20 (XEN) IOAPIC[0]: apic_id 2, version 32, address 0xfec00000, GSI 0-23 (XEN) Enabling APIC mode: Flat. Using 1 I/O APICs (XEN) Using scheduler: SMP Credit Scheduler (credit) (XEN) Detected 2485.797 MHz processor. (XEN) HVM: VMX enabled (XEN) VMX: MSR intercept bitmap enabled (XEN) I/O virtualisation disabled (XEN) CPU0: Intel(R) Core(TM)2 Quad CPU Q9300 @ 2.50GHz stepping 07 (XEN) Booting processor 1/2 eip 90000 (XEN) CPU1: Intel(R) Core(TM)2 Quad CPU Q9300 @ 2.50GHz stepping 07 (XEN) Booting processor 2/1 eip 90000 (XEN) CPU2: Intel(R) Core(TM)2 Quad CPU Q9300 @ 2.50GHz stepping 07 (XEN) Booting processor 3/3 eip 90000 (XEN) CPU3: Intel(R) Core(TM)2 Quad CPU Q9300 @ 2.50GHz stepping 07 (XEN) Total of 4 processors activated. (XEN) ENABLING IO-APIC IRQs (XEN) -> Using new ACK method (XEN) Platform timer overflows in 2 jiffies. (XEN) Platform timer is 1.193MHz PIT (XEN) Brought up 4 CPUs (XEN) *** LOADING DOMAIN 0 *** (XEN) elf_parse_binary: phdr: paddr=0xffffffff80200000 memsz=0x2f4d70 (XEN) elf_parse_binary: phdr: paddr=0xffffffff804f4d80 memsz=0x14c510 (XEN) elf_parse_binary: phdr: paddr=0xffffffff80642000 memsz=0xc08 (XEN) elf_parse_binary: phdr: paddr=0xffffffff80644000 memsz=0x11be8c (XEN) elf_parse_binary: memory: 0xffffffff80200000 -> 0xffffffff8075fe8c (XEN) elf_xen_parse_note: GUEST_OS = "linux" (XEN) elf_xen_parse_note: GUEST_VERSION = "2.6" (XEN) elf_xen_parse_note: XEN_VERSION = "xen-3.0" (XEN) elf_xen_parse_note: VIRT_BASE = 0xffffffff80000000 (XEN) elf_xen_parse_note: PADDR_OFFSET = 0xffffffff80000000 (XEN) elf_xen_parse_note: ENTRY = 0xffffffff80200000 (XEN) elf_xen_parse_note: HYPERCALL_PAGE = 0xffffffff80206000 (XEN) elf_xen_parse_note: FEATURES = "writable_page_tables|writable_descriptor_tables|auto_translated_physmap|pae_pgdir_above_4gb|supervisor_mode_k ernel" (XEN) elf_xen_parse_note: LOADER = "generic" (XEN) elf_xen_addr_calc_check: addresses: (XEN) virt_base = 0xffffffff80000000 (XEN) elf_paddr_offset = 0xffffffff80000000 (XEN) virt_offset = 0x0 (XEN) virt_kstart = 0xffffffff80200000 (XEN) virt_kend = 0xffffffff8075fe8c (XEN) virt_entry = 0xffffffff80200000 (XEN) Xen kernel: 64-bit, lsb, compat32 (XEN) Dom0 kernel: 64-bit, lsb, paddr 0xffffffff80200000 -> 0xffffffff8075fe8c (XEN) PHYSICAL MEMORY ARRANGEMENT: (XEN) Dom0 alloc.: 0000000222000000->0000000224000000 (122880 pages to be allocated) (XEN) VIRTUAL MEMORY ARRANGEMENT: -- Kind Regards Rudi Ahlers SoftDux Website: http://www.SoftDux.com Technical Blog: http://Blog.SoftDux.com Office: 087 805 9573 Cell: 082 554 7532

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