On the whole, system administrators tend to be skeptical of anything new. Literally everything, from new server platforms to software updates, is met with caution, until practical experience and positive feedback from colleagues in other companies emerge. Itâs understandable, as when you are literally responsible for the functionality of the business and the safety of important information, you eventually stop trusting even yourself, not to mention contractors, subordinates, or regular users.
Distrust towards software updates stems from numerous unpleasant instances where the installation of new patches led to reduced performance, changes in the user interface, failures of information systems, or, particularly unpleasant, data loss. However, completely abandoning updates isnât an option, as doing so could leave your enterprise's infrastructure vulnerable to cybercriminal attacks. One merely needs to recall the notorious WannaCry virus incident, when data stored on millions of computers that had not been updated to the latest version of Windows became encrypted. This incident not only cost the jobs of countless system administrators, but also clearly demonstrated the need to develop a new policy for updating software products within the enterprise that would balance security and the speed of installation. So, in anticipation of the release of the LTS version of Zimbra 8.8.15, let's take a look at how we can update the Zimbra Collaboration Suite Open-Source Edition to ensure the preservation of all critically important data.
Ăks Zimbra Collaboration Suite'i peamisi omadusi on, et praktiliselt kĂ”iki selle komponente saab dubleerida. Eriti on vĂ”imalik lisada LDAP-Master'ile dubleerivaid LDAP-replikaid, millele on vajadusel vĂ”imalik ĂŒle kanda pĂ”hja LDAP-serveri funktsioonid. Samuti on vĂ”imalik dubleerida Proxy-servereid ja MTA-servereid. Selline dubleerimine vĂ”imaldab vajaduse korral infrastruktuuri eraldi komponente uuendamise ajaks vĂ€lja lĂŒlitada ning seelĂ€bi kaitsta end mitte ainult pika seisaku, vaid ka andmete kaotuse eest ebaĂ”nnestunud uuendamise korral.
Erinevalt teistest infrastruktuuri komponentidest ei toeta Zimbra Collaboration Suite e-posti salvestuste dubleerimist. Ieven kui teie infrastruktuuris on mitmeid e-posti salvestusi, vĂ”ivad iga e-posti kasti andmed asuda vaid ĂŒhes kindlas salvestuses. serveris. SeetĂ”ttu on ĂŒks peamisi andmete sĂ€ilitamise reegleid uuendamise kĂ€igus Ă”igeaegne teabe varundamine e-posti salvestustes. Mida vĂ€rskem on teie varukoopia, seda rohkem andmeid jÀÀb alles, kui tekib erakorraline olukord. Siiski on siin nĂŒanss, et Zimbra Collaboration Suite'i tasuta vĂ€ljaandes ei ole sisseehitatud varundusmehhanismi ning varukoopia loomiseks tuleb kasutada GNU/Linux'i sisseehitatud tööriistu. Kui aga teie Zimbra infrastruktuuris töötab mitu e-posti salvestust ja e-posti arhiivi suurus on piisavalt suur, siis vĂ”ib iga selline varundamine vĂ”tta vĂ€ga kaua aega ja luua tĂ”sist koormust kohalikele vĂ”rkudele ja serveritele. Lisaks, pikaajalise kopeerimise kĂ€igus tĂ”usevad erinevate erakorraliste olukordade tekkimise riskid. Samuti, kui teha sellist varundamist teenuse peatamata, on oht, et rida faile vĂ”ib olla kopeeritud valesti, mis toob kaasa mĂ”ningate andmete kaotuse.
Just because of this, if you need to back up large amounts of data from mail storage, it is better to use incremental backups, which allow you to avoid a full copy of all data, instead backing up only the files that were created or changed after the last full backup. This significantly speeds up the backup process and allows for quicker installation of updates. Incremental backups in Zimbra Open-Source Edition can be achieved using the Zextras Backup modular extension included in Zextras Suite.
Another powerful tool, Zextras PowerStore, allows system administrators to deduplicate data on the mail storage. This means that all identical attachments and duplicate emails on the mail server will be replaced with a single original file, while all duplicates will become transparent symbolic links. As a result, this not only leads to significant disk space savings, but also greatly reduces the size of the backup, which allows for a decrease in the time taken for full backups and consequently making them much more frequent.
However, the main capability that Zextras PowerStore offers for safe updates is the transfer of mailboxes between mail servers in multi-server Zimbra infrastructures. With this feature, the system administrator can perform the same operations with mail storage as we did with MTA and LDAP servers for their safe updates. For example, if there are four mail storages in the Zimbra infrastructure, you can try distributing mailboxes from one of them to the other three, and when the first mail storage is empty, it can be updated without any concerns for data safety. If the system administrator has a backup mail storage in the infrastructure, it can be utilized as a temporary repository for mailboxes transferred from the mail storages being updated.
The console command that allows such transfers is DoMoveMailbox. Ette, et saaksite seda kasutada kÔigi kontode edastamiseks e-posti salvest, peate esmalt saama nende tÀieliku loendi. Selle saavutamiseks tÀitke e-posti serveris kÀsk zmprov sa zimbraMailHost=mailbox.example.com > accounts.txt. PÀrast selle tÀitmist saame faili accounts.txt , mis sisaldab kÔigi e-posti postkastide loetelu meie e-posti salvestuses. PÀrast seda saame seda kasutada kontode edastamiseks teise e-posti salvesse. See nÀeb vÀlja nÀiteks nii:
zxsuite powerstore doMailboxMove reserve_mailbox.example.com input_file accounts.txt stages data
zxsuite powerstore doMailboxMove reserve_mailbox.example.com input_file accounts.txt stages data,account notifications admin@example.com
KĂ€sku tĂ€idetakse kaks korda, et esmakordsel andmete kopeerimisel ei edastataks kontot, ning teisel korral, kuna andmete edastamine toimub inkrementaalselt, kopeeritakse kĂ”ik andmed, mis ilmusid pĂ€rast esimest edastamist, ja seejĂ€rel edastatakse ka kontod. Juhime tĂ€helepanu sellele, et konto edastamine kaasneb lĂŒhikese ajavahemikuga e-posti postkasti kĂ€ttesaamatusega, seega on mĂ”istlik kasutajaid sellest teavitada. Lisaks saadetakse pĂ€rast teise kĂ€su tĂ€itmist administraatori e-posti seonduv teavitusteade. TĂ€nu sellele saab administraator maksimaalselt kiiresti alustada e-posti salvestuse uuendamist.
Kui e-posti salvestuse tarkvara uuendamine toimub SaaS-teenuse pakkuja poolt, on palju mÔistlikum andmete edastamine mitte kontode jÀrgi, vaid domeenide kaupa, mis seal asuvad. Sellisteks eesmÀrkideks piisab veidi muudetud kÀsust:
zxsuite powerstore doMailboxMove reserve_mailbox.saas.com domains client1.ru, client2.ru, client3.ru stages data
zxsuite powerstore doMailboxMove secureserver.saas.com domains client1.ru, client2.ru, client3.ru stages data,account notifications admin@saas.com
PÀrast seda, kui kontode ja nende andmete edastamine e-posti salvestusest on toimunud, lakab andmed algses serveris olemast mingit vÀÀrtust ja saate alustada e-posti serveri uuendamist ilma mureta nende sÀilitamise pÀrast.
Nende jaoks, kes soovivad minimeerida seisakuaega e-posti postkastide edastamisel, sobib ideaalselt fundamentaalselt erinev kĂ€su kasutamise stsenaarium zxsuite powerstore doMailboxMove, mille sisu seisneb selles, et e-posti postkastid viiakse kohe uuendatud serveritesse, ilma vaheserverite kasutamise vajaduseta, serverid. TeisisĂ”nu, me lisame Zimbra infrastruktuuri uue e-posti salvestusruumi, mis on juba ajakohastatud viimane versioon, ja seejĂ€rel viime lihtsalt juba tuttava stsenaariumi jĂ€rgi ĂŒle arvestused vanalt serverilt ning kordame protseduuri, kuni kĂ”ik infrastruktuuri serverid on uuendatud.
Selline lĂ€henemine vĂ”imaldab kontode ĂŒleviimist teha ĂŒhe korra ning seetĂ”ttu vĂ€hendada aega, mille jooksul postkastid jÀÀvad kĂ€ttesaamatuks. Lisaks on selleks vajalik vaid ĂŒks tĂ€iendav e-posti server. Siiski peaks ettevaatlik olema nende administraatorite suhtes, kes deployivad e-posti salvestusruume erinevate konfiguratsioonidega serverites. Asi on selles, et suures koguses kontode ĂŒleviimine nĂ”rgemale serverile vĂ”ib negatiivselt mĂ”jutada teenuse kĂ€ttesaadavust ja reageerimiskiirust, mis vĂ”ib olla ĂŒsna kriitiline suurte ettevĂ”tete ja SaaS-teenusepakkujate jaoks.
Nii saavad Zextras Backup ja Zextras PowerStore abil Zimbra sĂŒsteemiadministraatorid uuendada kĂ”iki Zimbra infrastruktuuri sĂ”lmi ilma igasuguste riskideta nendele salvestatud teabe sĂ€ilitamise osas.
Allikas: habr.com
