Top Document: comp.unix.aix Frequently Asked Questions (Part 3 of 5) Previous Document: 1.703: Chlv warning. Is the first 4k of a LV safe? Next Document: 1.705: Why am I having trouble adding another disk to my VG? See reader questions & answers on this topic! - Help others by sharing your knowledge 1016 Physical Partitions Per Disk in a Volume Group: In the design of LVM, each Logical Partition maps to one Physical Partition. And, each Physical Partition maps to a number of disk sectors. The design of LVM limits the number of Physical Partitions that LVM can track PER DISK in a volume group to 1016. In most cases, not all the possible 1016 tracking partitions are used by a disk. The default size of each Physical Partition during a "mkvg" command is 4 MB, which implies that individual disks up to 4 GB can be included into a volume group. If a disk larger than 4 GB is added to a volume group (based on usage of the default 4 MB size for Physical Partition) the disk addition will fail with a warning message that the Physical Partition size needs to be increased.* There are two instances where this limitation will be enforced. The first case is when the user tries to use "mkvg" to create a volume group where the number of physical partitions on one of the disks in the volume group would exceed 1016. In this case, the user must pick from the available Physical Partition ranges of: 1, 2, (4), 8, 16, 32, 64, 128, 256 Megabytes and use the "-s" option to "mkvg". The second case is where the disk which violates the 1016 limitation is attempting to join a pre-existing volume group with the "extendvg" command. The user can either recreate the volume group with a larger Physical Partition size (which will allow the new disk to work with the 1016 limitation) or the user can create a standalone volume group (consisting of a larger Physical Partition size) for the new disk. In AIX 4.1 and 3.2.5, if the install code detects that the rootvg drive is larger than 4 GB, it will change the "mkvg -s" value until the entire disk capacity can be mapped to the available 1016 tracks.** This install change also implies that all other disks added to rootvg, regardless of size, will also be defined at that new Physical Partitions size. For RAID systems, the /dev/hdiskX name used by LVM in AIX may really consist of many non-4GB disks. In this case, the 1016 limitation still exists. LVM is unaware of the size of the individual disks that may really make up /dev/hdiskX. LVM bases the 1016 limitation on the AIX recognized size of /dev/hdiskX, and not the real independent physical disks that make up /dev/hdiskX. The questions asked of this issue are: 1) What are the symptoms of this problem? 2) How safe is my data? What if I never use mirroring or migratepv? 3) Can I move this volume group between RS/6000 systems and versions of AIX? Here are the answers: A) What are the symptoms of this problem? The 1016 VGSA is used to track the "staleness of mirrors". If you are in violation of 1016, you may possibly get a false report of a non-mirrored logical volume being "stale" (which is an oxymoron) or you may get a false indication that one of the your mirror copies has gone stale. Next, migratepv may fail because migratepv briefly uses mirroring to move a logical volume from one disk to another. If the target logical partition is incorrectly considered "stale", then the migratepv cannot remove the source logical partition and the migratepv command will fail in the middle of migration. B) How safe is my data? What if I never use mirroring or migratepv? The data is as safe (in your mind) as the day before you found out about 1016 violations. The only case where data may be lost is if one is mirroring a logical volume and ALL copies go bad at the same time and LVM isn't aware of it because the copies that go bad are beyond the 1016 tracking range. However, in this case, you would lose data even if you were within the 1016 range. If you never mirror or use migratepv, then this issue shouldn't concern you. But, it might be unwise to state you'll NEVER use either of those options. C) Can I move this volume group between RS/6000 systems and versions of AIX? Yes you can. The enforcement of this 1016 limit is only during mkvg and extendvg. The "safeness" of the data on the volume group on AIX 3.2 is the same as it is on AIX 4.1. * This bug was fixed in apar ix48926. Current AIX 3.2.5 and 4.1.1, which do not have this fix on applied, will allow the creation of volume groups with more than 1016 partitions. The implication of this bug allowing more than 1016 physical partitions is that the user may access all portions of the logical volume. However during disk mirroring, the status of partitions beyond the 1016 limit will not be tracked correctly. If mirrors beyond the 1016 range become "stale", LVM will not be aware of their condition and data consistency may become an issue for those partitions. Additionally, the "migratepv" command creates mirrors and deletes them as a method for moving logical volumes around within/between disks. If the 1016 limit is violated, then the "migratepv" command may not behave correctly. The user should pick up apar ix51754, which clarifies the error message when this condition is detected. Additionally, the user can read the non-ptf documentation apar ix50874 which is a companion to ix48926 and ix51754. ** This bug was fixed for AIX 3.2.5 rootvg install in apars ix46862 and ix46863. This bug does not exist in AIX 4.1.1. User Contributions:Comment about this article, ask questions, or add new information about this topic:Top Document: comp.unix.aix Frequently Asked Questions (Part 3 of 5) Previous Document: 1.703: Chlv warning. Is the first 4k of a LV safe? Next Document: 1.705: Why am I having trouble adding another disk to my VG? Part1 - Part2 - Part3 - Part4 - Part5 - Single Page [ Usenet FAQs | Web FAQs | Documents | RFC Index ] Send corrections/additions to the FAQ Maintainer: bofh@mail.teleweb.pt (Jose Pina Coelho)
Last Update March 27 2014 @ 02:11 PM
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This sunday, quite possibly 28, 2019 snapshot, Provided by the city service group, jointly for Jarniyah, contains been authenticated based on its contents and other AP reporting, Shows Syrians lifetime extinguish a fire in a field of crops, wearing Jaabar, Raqqa state, Syria. Thousands of acres of wheat and barley fields in both Syria and Iraq have been scorched by the fires within harvest season, that typically runs until mid June. "The life that we live here is already bitter, " stated Hussain Attiya, A farmer from Topzawa Kakayi in upper Iraq. "If the outcome continues like this, I would say that no one will continue to be here. I plant 500 to 600 acres on a yearly basis. still, I won't be able to do that because I can't stay here and guard the land day and night. "ISIS militants have a history of working with a "Scorched earth insurance coverage " In areas from that they can retreat or where they are defeated. Ahmed al Hashloum thoughts Inmaa, Arabic for benefits, A local civil group that supports farming. all it takes is a cigarette butt to set haystacks on fire, He brought up. Said the fires are threatening to disrupt normal food production cycles and potentially reduce food to protect months to come. The crop burning remains localized and can't be compared to pre war devastation, Beals considered that. "suffice to say, It is only the beginning of the summer and if the fires continue it could lead to a crisis, " Beals recounted,AlternativeHeadline,prepared crop burning blamed on ISIS remnants compounds misery in war torn Iraq and Syria"}
But good news is short lived in this part of the world, Where residents of the two countries struggle to face seemingly never ending violence and turmoil amid Syria's civil war and attacks by remnants of the Islamic State of Iraq and Syria (ISIS) social groups. of course, Even in locations where conflict has subsided, Fires currently raging in farmers' fields, depriving them of valuable crops.
The blazes have been blamed also consider on defeated ISIS militants seeking to avenge their losses, Or on Syrian regime forces battling to rout other armed groups. Thousands of acres of wheat and barley fields in both Syria and Iraq have been scorched by the fires within harvest season, what kind runs until mid June.
ISIS militants have a history of implementing a "Scorched earth guideline" In areas from which retreat or where they are defeated. this "A means of inflicting a collective punishment on those put aside, said Emma Beals, a completely independent Syria researcher.
ISIS militants claimed obligations for burning crops in their weekly newsletter, al Nabaa, Saying they targeted farms owned by senior officials in six Iraqi provinces and in Kurdish administered eastern Syria, sending the persistent threat from the group even after its territorial defeat.
ISIS said it burned the farms of "The apostates in Iraq together with the Levant" And required more.
"It seems that it'll be a hot summer that will burn the pockets of the apostates as well as their hearts as they burned the Muslims and their homes in the past years, this great article said.
countless acres of wheat fields around Kirkuk in northern Iraq were set on fire. Several wheat fields in the Daquq district in southern Kirkuk burned for three days straight yesterday.
In eastern Syria's Raqqa state, Farmers battled raging fires with items of cloth, bags and water trucks. Piles of hay burned and black smoke billowed above the job areas.
The Syrian Observatory for Human Rights said through 74,000 acres (30,000 hectares) linked farmland in Hassakeh, Raqqa and completely to Aleppo province to the west, Were scorched.
Activist Omar Abou Layla said local Kurdish led forces failed to react to the fires in the province of Deir el Zour, Where ISIS was uprooted from its last property in March, (...)