msgid "" msgstr "" "Project-Id-Version: PACKAGE VERSION\n" "POT-Creation-Date: 2010-10-21 23:56+0600\n" "PO-Revision-Date: 2010-10-21 23:46+0600\n" "Last-Translator: Automatically generated\n" "Language-Team: none\n" "Language: ru\n" "MIME-Version: 1.0\n" "Content-Type: text/plain; charset=UTF-8\n" "Content-Transfer-Encoding: 8bit\n" "Plural-Forms: nplurals=3; plural=(n%10==1 && n%100!=11 ? 0 : n%10>=2 && n" "%10<=4 && (n%100<10 || n%100>=20) ? 1 : 2);\n" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(title):6 msgid "Multipathing for Gentoo" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(author:title):8 #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(author:title):11 #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(author:title):14 #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(author:title):17 msgid "Author" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(mail:link):9 msgid "tsunam" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(mail:link):12 msgid "matthew.summers@liquidustech.com" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(mail):12 msgid "Matthew Summers" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(mail:link):15 msgid "richard.anderson@liquidustech.com" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(mail):15 msgid "Richard Anderson" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(mail:link):18 msgid "steve.rucker@liquidustech.com" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(mail):18 msgid "Steve Rucker" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(author:title):20 msgid "Editor" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(mail:link):21 msgid "nightmorph" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(abstract):24 msgid "" "This document teaches you how to set up multipathing services for data " "storage." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(version):32 msgid "1" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(date):33 msgid "2008-09-10" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(title):36 msgid "Introduction" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):40 msgid "" "Multipathing services, generally deployed in enterprise environments, " "provide a means for high performance, load-balanced, and fault-tolerant data " "storage either locally or via a storage area network (SAN). Multipathing " "facilitates a single storage device to be transparently accessed across one " "or more paths. For example, if there are two connections from a server Host " "Bus Adapter (HBA) to two Fibre Channel switches and then to a SAN, when the " "HBA module loads and scans the bus, it will read four paths to the SAN: the " "paths from the server HBA to and from each Fibre Channel switch and at the " "storage device. Taking advantage of this situation, Multipath allows you to " "make use of each path simultaneously or independently to ensure a constant " "and reliable connection to the data in storage. Multipath serves as a " "failover for all connections points in the event of losing one path making " "critical data always available due to redundancy in the design and " "implementation." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):56 msgid "" "In the most basic sense, multipathing is made of two distinct parts: " "device-mapper and multipath-tools. Device Mapper is the " "first key element of this application. Administrators are probably familiar " "with Device Mapper from LVM, EVMS, dm-crypt, or in this case, Multipath. In " "short, working within the kernel space Device Mapper takes one block device " "such as /dev/sda (as all SAN based targets will be some type of " "SCSI device) and maps it to another device." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):66 msgid "" "On a lower level, Device Mapper creates a virtual block device accepting all " "of the commands of a regular block device, but passes on the actual data to " "the real block device. As previously stated, the mapping process is all " "handled in the kernel space and not in user space." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):73 msgid "" "Multipath Tools is a set of userspace tools that interacts with the " "Device Mapper tools and creates structures for device handling, implementing " "I/O multipathing at the OS level. In a typical SAN environment, you will " "have multiple paths to the same storage device: a fiber card (or two) on " "your server that connects to a switch which then connects to the actual " "storage itself (as in the scenario discussed above). So administrators could " "possibly see the same device one to four times in such a situation (each " "card will see the LUN twice, once for each path it has available to it). " "Thus, a single drive could be recognized as sda, sdb, sdc, and sdd. If you were to mount /" "dev/sda to /san1, for instance, you would be going over " "the singular path from one fiber card to a switch and then to a port on the " "same storage device. If any of those points were to fail, you would lose " "your storage device suddenly and have to unmount and remount with another " "device (sdb)." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):90 msgid "" "Consequently, this scenario is not ideal as you are only using one out of " "the four possible paths. This is where the combination of Multipath tools " "and Device Mapper are beneficial. As already explained, Device Mapper " "creates virtual block devices and then passes information to the real block " "devices." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(title):102 msgid "Installation and Configuration" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(title):104 msgid "Installation and Tools" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):107 msgid "" "You need to emerge multipath-tools and sg3_utils. On the disk, " "you want to find the wwid. You can use sq_vpd (provided by " "sg3_utils) to do this." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(pre:caption):113 msgid "Installing multipath-tools and initial configuration" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(pre):113 #, no-wrap msgid "" "\n" "# emerge multipath-tools sg3_utils\n" "(Replace /dev/DEVICE with your disk to find its wwid)\n" "# /usr/bin/sq_vpd ?page=di /dev/DEVICE\n" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):119 msgid "" "Where DEVICE is the sd device, the ID will come back with a 0x6. " "Replace 0x with 3, and you will have the proper ID that you'll " "put into the multipath wwid in /etc/multipath.conf. More " "on this in the next chapter." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(title):129 msgid "Configuring Gentoo for multipathing" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):132 msgid "" "To configure Gentoo for multipath, your kernel needs the following settings:" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(pre:caption):136 msgid "Adding multipath support" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(pre):136 #, no-wrap msgid "" "\n" "Device Drivers --->\n" " SCSI device support --->\n" " <*> SCSI target support\n" " <*> SCSI disk support\n" " [*] Probe all LUNs on each SCSI device\n" " [*] Multiple devices driver support (RAID and LVM) --->\n" " <*> Multipath I/O support\n" " <*> Device mapper support\n" " <*> Multipath target\n" " (Select your device from the list))\n" " <*> EMC CX/AX multipath support \n" " <*> LSI/Engenio RDAC multipath support \n" " <*> HP MSA multipath support\n" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(note):152 msgid "" "scsi_id is done by targets. IDE drives have two spots to which you " "can connect. An administrator has the ability to set a drive as a master and " "another drive as a slave or set to autoselect by changing the dip switches. " "scsi_id is similar. Each drive or Logical Unit Number (LUN) has a unique ID, " "which ranges from 0 to 254. A device that has ID 0 will be discovered before " "a device that has, for example, ID 120, because it performs a LIP (a scan of " "the SCSI bus for devices that respond) that starts from 0 and works its way " "upwards." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):162 msgid "" "In the kernel menu config, make sure CONFIG_SCSI_MULTI_LUN=y is set to " "ensure the SCSI subsystem is able to probe all Logical Unit Numbers (LUNs) " "(This is recommended as you'll stop scanning after ID 0 if you have a device " "on an ID of 0 but not 1 and then on an ID of 2. Simply, " "you'll get your device for ID 0 but not 2.) or whichever " "device you need for SCSI, such as a QLogic 2400 card, which is in the SCSI " "low-level drivers area." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):171 msgid "For a better understanding, consider the following scenarios:" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):175 msgid "" "There are three drives with IDs of 0,1,2. Without the \"probe all LUNs\" " "setting, you will see IDs 0,1,2 as sda,sdb,sdc - all devices are seen. If " "you delete the ID 1 drive. IDs 0,2 will still be seen. It might seem to make " "sense that you would see sda and sdb now (sdc would move to sdb as there is " "no device to fill it up). However, if you don't probe all LUNs, it will " "perform in the following manner:" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):184 msgid "" "Scenario 1: Without \"probe all LUNs\", the scan will start and ID 0 will be " "seen. ID 0 will be set to sda and then move to find ID 1. If ID 1 is not " "detected, scanning will stop and be considered complete having perceived to " "have scanned all devices even if there is a device on ID 2 or any other " "subsequent ID. Reboot for scenario two." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):192 msgid "" "Scenario 2: If you have \"probe all LUNs\", the scan will start and detect " "ID 0. This ID will be assigned sda and will continue to detect the next " "device. If ID 1 is not detected, scanning will continue to find more " "devices. ID 2 will be located and assigned to be sdb. If no devices (IDs) " "are detected beyond that, scanning will be considered complete." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(note):200 msgid "" "Although it seems that it is unfeasible or even unnecessary to have devices " "spaced many LUNs apart, to account for all options it is necessary to still " "probe all LUNs. An administrator will encounter many reasons (business or " "personal) for such a setup. Therefore, the second scenario would be optimal " "to ensure that all devices are recognized and assigned an ID in the " "multipath setup process." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):209 msgid "" "So, once you probe all LUNs, all devices will be recognized and assigned an " "ID in Multipath." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(title):219 msgid "Architectural Overview" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):223 msgid "" "As part of Multipath Tools, there are priority groups filled with the " "devices mentioned earlier. After you have configured multipath-tools " "and started it with /etc/init.d/multipath start, you can list the " "groups via multipath -l. The output will look like the following:" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(pre:caption):230 msgid "multipath -l output" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(pre):230 #, no-wrap msgid "" "\n" "EVA_SAN (3600508b4001044ee00013000031e0000)\n" "[size=300 GB][features=\"1 queue_if_no_path\"][hwhandler=\"0\"]\n" "\\_ round-robin 0 [active]\n" "\\_ 0:0:0:1 sda 8:0 [active]\n" "\\_ round-robin 0 [enabled]\n" "\\_ 0:0:1:1 sdb 8:16 [active]\n" "\n" "EVA_SAN2 (3600508b4001044ee0001300003880000)\n" "[size=300 GB][features=\"1 queue_if_no_path\"][hwhandler=\"0\"]\n" "\\_ round-robin 0 [active]\n" "\\_ 0:0:0:2 sdc 8:32 [active]\n" "\\_ round-robin 0 [enabled]\n" "\\_ 0:0:1:2 sdd 8:48 [active]\n" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):246 msgid "" "By default, it will pick the first priority group (the first top round-robin " "for the EVA_SAN2, for instance, being sdc). In this instance, " "due to round robin it will bounce back and forth. But if one path was to " "fail, it would push all information to the other path and continue. Only if " "all the devices in a path fail will it actually fail and go to the secondary " "priority group." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(title):257 msgid "Typical Configuration" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):260 msgid "A typical Multipath configuration looks like the following:" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(pre:caption):264 msgid "A typical /etc/multipath.conf file" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(pre):264 #, no-wrap msgid "" "\n" "defaults {\n" "udev_dir /dev\n" "polling_interval 15\n" "selector \"round-robin 0\"\n" "path_grouping_policy group_by_prio\n" "failback 5\n" "path_checker tur\n" "prio_callout \"/sbin/mpath_prio_tpc /dev/%n\"\n" "rr_min_io 100\n" "rr_weight uniform\n" "no_path_retry queue\n" "user_friendly_names yes\n" "}\n" "blacklist {\n" "devnode cciss\n" "devnode fd\n" "devnode hd\n" "devnode md\n" "devnode sr\n" "devnode scd\n" "devnode st\n" "devnode ram\n" "devnode raw\n" "devnode loop\n" "devnode sda\n" "}\n" "\n" "multipaths {\n" "multipath {\n" "wwid\n" "(To find your wwid, please use /usr/bin/sq_vpd ?page=di /dev/DEVICE.\n" "The address will be a 0x6. Remove the 0x and replace it with 3.)\n" "alias DB_SAN\n" "}\n" "devices {\n" "device {\n" "(White spacing is important on these two items to match the vendor specifications.)\n" "\"IBM \"\n" "\"1815 FAStT \"\n" "}\n" "}\n" "}\n" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(impo):309 msgid "" "On your devices, it is best to cat/sys/block/sd(device)/device/" "model and cat/sys/block/device/sd(device)/device/vendor, placing both directly into your devices section in /etc/" "multipath.conf. You might not always see the white spacing, and it's " "part of the name in this case. One reason for the device section is that not " "every vendor's string is in the kernel convention and naming, and the " "string, as such, is not always detected as required." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):320 msgid "" "A typical multipath configuration utilizing an EVA_SAN where the device " "information is in the kernel information regarding SAN hardware detection " "would look like:" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(pre:caption):326 msgid "EVA_SAN configuration" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(pre):326 #, no-wrap msgid "" "\n" "multipaths {\n" "multipath {\n" "wwid 3600508b4001044ee00013000031e0000\n" "alias EVA_SAN\n" "}\n" "multipath {\n" "wwid 3600508b4001044ee0001300003880000\n" "alias EVA_SAN2\n" "}\n" "}\n" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(title):344 msgid "Setting Up Your Own Configuration" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):348 msgid "" "The multipath configuration is fairly simple to accomplish because the only " "file that needs modification is /etc/multipath.conf." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):353 msgid "" "To begin, set the polling interview to how often (in seconds) path " "checks will be performed to ensure that the path is alive and healthy." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):358 msgid "selector will be set at \"round-robin 0\"." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(note):362 msgid "" "This round-robin value is the only selector value that will be used in this " "configuration." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):367 msgid "" "prio_callout: This one can be quite important, and there are a number " "of different priorities for different devices, such as:" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(li):373 msgid "mpath_prio_alua" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(li):374 msgid "mpath_prio_emc" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(li):375 msgid "mpath_prio_hds_modular" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(li):376 msgid "mpath_prio_netapp" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(li):377 msgid "mpath_prio_tpc" msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(note):380 msgid "" "For most people, mpath_prio_tpc will suffice as it's a conservative " "checker. Other devices like mpath_prio_netapp have special " "functionality for priority grouping, such as netapps." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):386 msgid "" "path_grouping_policy has a few different options: failover, multibus, " "group_by_prio. Failover will only have one disk per priority group. " "Multibus will put all devices into one priority group. " "Group_by_prio is done by a \"priority value.\" So routes that have " "the same priority value will be grouped together, the priority values being " "determined by the callout." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):395 msgid "" "no_path_retry is set to queue as most people don't want data " "to fail to send at all. So, if all paths fail, for instance, the I/Os will " "queue up until the device returns and then sends everything again. Depending " "on your transfer, this can cause load issues." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):402 msgid "" "rr_min_io are the number of I/Os to do per path before switching to " "the next I/Os in the same group. If sda and sdb " "were in the same group, rr_min_io would do 100 I/Os to sda then " "do 100 to sdb, bouncing back and forth. This is a setting to " "tweak for each instance to maximize performance because the data load and " "size of transfers/request vary by company. The default in the case is " "1000, but some may prefer a smaller number in order to switch ports " "more often, when possible." msgstr "" #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(p):413 msgid "" "user_friendly_names make it easier to see which device you are " "working with. For example, if you set user_friendly_names to no, then " "you'll see WWID instead of EVA_SAN for your device." msgstr "" #. Place here names of translator, one per line. Format should be NAME; ROLE; E-MAIL #: ../../gentoo/xml/htdocs/doc/en//multipath.xml(None):0 msgid "translator-credits" msgstr ""