• How Does Cisco CUCM (Cisco Unified Communication Manager) Work?


    Cisco's CUCM (Cisco Unified Communication Manager) is a system that combines voice, video, data and mobile products into a single unified management suite. At its core, the CUCMis like a "Super PBX" that controls the flow of all communications through an organization even single or multiple site deployments. Cisco's CUCMmakes communication more effective and simple through centralized management and unification of communications resources.........
  • gvfs mount in /run/user cannot be accessed or displayed wrong permissions


    The folder contents could not be displayed Backend currently unmounting drwx------ 10 userhere group 260 Aug 23 19:40 .. ?????????? ? ? ? ? ? sftp:host=192.168.8.80,user=adhoc ls: cannot access 'sftp:host=192.168.8.80,user=adoc': Input/output error $ ps aux|grep fuse one 253........
  • VMWare vSphere 6.7 Errors Solution 503 Service Unavailable (Failed to connect to endpoint:


    503 Service Unavailable (Failed to connect to endpoint: [N7Vmacore4Http20NamedPipeServiceSpecE:0x00005556ba09c070] _serverNamespace = / action = Allow _pipeName =/var/run/vmware/vpxd-webserver-pipe) 503 Service Unavailable (Failed to connect to endpoint: [N7Vmacore4Http16LocalServiceSpecE:0x00007fd26000b240] _serverNamespace = /ui action = Allow _port = 5090) Errors like the above are usually because there is an issue with your vSphere or more commonly it i........
  • iptables guide and examples and howto


    iptables allow port 22 example Of course change --dport and -s to suit your needs #allow certain IP to access port 22 iptables -A INPUT -p tcp -m tcp --dport 22 -s 192.168.1.0/24 -j ACCEPT # block others iptables -A INPUT -p tcp --dport 22 -j DROP........
  • VMWare 6.7 VCSA VSphere ESXi Management SSO Install Guide on Linux using the CLI


    #mount the VCSA DVD mount /dev/sr0 /mnt/cd #alternatively you could mount the iso directly mount -o loop vcsa.iso /your/mount/path #for this purpose we are using the CLI installer on Linux cd /mnt/cd/vcsa-cli-installer/lin64 #no it's not going to be that easy you can't just run vcsa-deploy like that you need to use a template or configured .json file ./vcsa-deploy Usage: vcsa-deploy [-h] [--version] [--supported-deploymen........
  • USB Device/MP3 Player not working properly and can't browse the device filesystem? Check the cable twice and again!


    Here is a simple MP3 player and now there's a reason to understand why the supplied cable has some kind of capacitor and is very short. These devices can be VERY finicky and any voltage fluctuation or difference is enough to cause issues. Take for example the error messages from Linux Mint: [804829.895414] usb 1-1: USB disconnect, device number 11 [806961.109030] usb 1-1: new high-speed USB device number 12 using xhci_hcd........
  • Avocent DSR8020 KVM/IP - Network Connect Error - Solution


    This error is commonly due to Java security or TLS settings but there is a second issue with forwarded ports that also causes it. 1. Java Security/TLS Settings issue: This article has the solution to change them all in Linux automatically 2. Port Forwarding Issue if your Avocent DSR is behind NAT/private IP........
  • ADATA SU800 256GB 3D NAND Flash SSD Test & Review


    I keep reading these drives are slower, but they are cheap and still SSDand work very fast for my needs. As you can see the sequential read is 481-491MB/s, if I put them in MDADM RAID10 mode (normal RAID1) they should give me well over 900MB/s and with redundancy and being very cheap for what they offer. [1232206.315622] scsi 8:0:1:0: Direct-Access ATA ADATA SU800&........
  • iptables how to forward localhost port to remote public IP


    iptables -t nat -A OUTPUT -m addrtype --src-type LOCAL --dst-type LOCAL -p tcp --dport 3306 -j DNAT --to-destination ip.ip.ip.ip iptables -t nat -A POSTROUTING -m addrtype --src-type LOCAL --dst-type UNICAST -j MASQUERADE sysctl -w net.ipv4.conf.all.route_localnet=1 Make sure you substitute "ip.ip.ip.ip" for your real public IP and also the "--dport 3306" for the port you want to forward. Finally run the sysctl command and........
  • iptables port forwarding multiple ports to another IP


    iptables -t nat -A PREROUTING -p tcp -m multiport --dports 80,443,2068,8192 -j DNAT --to-destination 192.168.1.175 Just adjust the "--dports" to the ports you need and the --to-destination to the destination IP (note it must be on the same network as the server running iptables........
  • Openvz iptables v1.4.7: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. solution


    iptables -t nat -A PREROUTING -p tcp -m tcp -d 192.168.2.1/32 --dport 3389 -j DNAT --to-destination 192.168.5.2:3389 iptables v1.4.7: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. The above is often because you don't have the correct modules loaded on the hostnode or enabled for the container but in some cases it's actually a weird openvz setting. Che........
  • CPanel Link to all of the command line options


    CPanel says you can access 98% of the functions through CLI which experienced Unix/Linux admins prefer for simplicity and for scripting.  I've never found CPanel easy to use from the admin panel, it seems everything is hard to find and a simple task becomes a series of hunts. So for people like me here's the list: http://cpanel.net/system-administrators/command-line-scrip........
  • iptables how to forward port to another IP address with DNAT


    -A PREROUTING -d 98.98.98.5/32 -p tcp -m tcp --dport 1050 -j DNAT --to-destination 192.168.1.50:3389 The above forwards port 1050 on IP98.98.98.5 to 192.168.1.50 port 3389 (you can obviously edit things to meet your needs).........
  • What a hdd hard drive and mdadm RAID array failure looks like in Linux


    [3805108.257042] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB) [3805108.257052] sd 0:0:0:0: [sda] Write Protect is off [3805108.257054] sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00 [3805108.257066] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [3805108.257083] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB) [3805108.257090] sd 0:0:0:0: [sda] Write Protect is off........
  • iptables howto multiport forward in single line example


    -A PREROUTING -p tcp -m multiport --dports 10000,18080,13306 -j DNAT --to-destination 192.168.5.83........
  • iptables centos error getsockopt failed strangely: Invalid argument


    iptables -t nat -A PREROUTING -p udp -m multiport --dports 20,123,443 -j REDIRECT --to-port 53 getsockopt failed strangely: Invalid argument........
  • iptables redirect ports to a different host and port + NAT Masquerade howto/solution


    This is important if you need public access to internal IPs such as at your office and don't want to use a VPN just to SSHinto different servers: Below forwards the port "10001" to the IP192.200.5.53 on port 22 (of course adjust it to your needs). iptables -t nat -A PREROUTING -p tcp --dport 10001 -j DNAT --to-destination 192.200.5.53:22 Remember to enable MASQUERADE on your NAT IPs or they won't be able to talk to the outside world (........
  • WD 20EARX Dead Again


    Another new drive bad from the start: Jun 2 15:14:18 one-desktop kernel: [15895.386779] ata2.00: exception Emask 0x50 SAct 0x1 SErr 0x280900 action 0x6 frozen Jun 2 15:14:18 one-desktop kernel: [15895.386782] ata2.00: irq_stat 0x08000000, interface fatal error Jun 2 15:14:18 one-desktop kernel: [15895.386784] ata2: SError: { UnrecovData HostInt 10B8B BadCRC } Jun 2 15:14:18 one-desktop kernel: [15895.386788] ata2.00: cmd 60/0........
  • Dying Seagate 7200.11 SD15


    [137392.910057] ata4.00: exception Emask 0x0 SAct 0x1 SErr 0x80000 action 0x6 frozen [137392.910077] ata4: SError: { 10B8B } [137392.910095] ata4.00: cmd 60/20:00:00:00:00/00:00:00:00:00/40 tag 0 ncq 16384 in [137392.910099] res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout) [137392.910122] ata4.00: status: { DRDY } [137392.910135] ata4: hard resetting link [137393.440060] ata4: SATA link........
  • mdadm RAID 1 adventures


    I separated the 2 drives in the RAID 1 array. 1 is the old one /dev/sda and is out of date, while the separated other one /dev/sdc was in another drive and mounted and used with more data (updated). I wonder how mdadm will handle this: usb-storage: device scan complete md: md127 stopped. md: bind md: md127: raid array is not clean -- starting background reconstruction raid1: raid set md127 active with 1 out of 2 m........
  • Ubuntu 10.04 Linux is still not ready for the Desktop world


    I am a huge fan of Linux and the idea of OpenSource but I've said it many times, there are still hurdles in today in 2010 for Linux as a Desktop. Linux is still intended for servers at its very core. This can be changed succesfully though, as Apple has shown us with Mac OS X based on FreeBSD. Half of the issue is lack of driver support and the other half is the Linux Kernel and Window Manages, KDE and GNome still both don't cut it (but they're getting closer). I'll........
  • mencoder Linux CLI video editing how to encode video file into xvid and split by time into multiple parts


    Mencoder is great, you can throw anything at it, including video files from your camera and have it encode into xvid or almost any other format. In my case I took 640x480 video from my Canon and reduced the size by 1/3 with the options below (there are many other options that you can read about in the manual but I like to keep it simple). Mencoder Encode mencoder -ovc xvid -oac mp3lame -xvidencopts fixed_quant=4 -o ........
  • mdadm when a RAID 1 member dies


    [27969.398749] sd 5:0:0:0: [sdb] 3907029168 512-byte hardware sectors (2000399 MB) [27969.398749] sd 5:0:0:0: [sdb] Write Protect is off [27969.398749] sd 5:0:0:0: [sdb] Mode Sense: 00 3a 00 00 [27969.398749] sd 5:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [27972.117543] ata6.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0 [27972.117543] ata6.00: irq_stat 0x48000000 [27972.117543] ata6.00: cmd 60/08:00:ff:7........
  • Seagate Drive 500GB Drive Dying


    This drive is clearly on the way out, the Kernel knows it but I'm surprised that SMART is not concerned. I didn't blame Seagate for their past issues until now. This hard drive has hardly been used and has not even been powered on for a year according to SMART. Home page is http://smartmontools.sourceforge.net/ === START OF INFORMATION SECTION === Model Family: Seagate Barracuda 7200.11 Device........
  • Linux AHCI Hotswap Tips - Remember To Reread The Partition Table WITHOUT rebooting


    From the package "parted" you can use the command "partprobe" to re-read the partition table. I really hate rebooting, and that's what Iloved to hear about AHCI motherboards, that they allow hotswap so you don't have to reboot. But that's only as good as the OS, if the OS does not reload the partition table you won't be able to do anything with that new drive you attached without rebooting. Yes, even without re-reading the partiton table Linux will........
  • Basic Port Listing


    Basic Port ListingHopefully someone finds this useful or at least interesting. http://www.sans.org/top20/#u9 Name Port Protocol Description Small services ........
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