StatefulSet如何提供稳定的网络标识和状态

ReplicaSet中的Pod都是无状态，可随意替代的。又因为ReplicaSet中的Pod是根据模板生成的多副本，无法对每个副本都指定单独的PVC。

来看一下StatefulSet如何解决的。

提供稳定的网络标识#

StatefulSet创建Pod都有一个从零开始的顺序索引，这会体现在Pod的名称和主机名上，同样也会体现在Pod对应的固定存储上。所以这些名字是可预先知道的，不同于ReplicaSet的随机生成名字。

因为他们的名字都是固定的，而且彼此状态都不同，通常会操作他们其中的一个。如此情况，一般都会创建一个与之对应的headless Service，通过这个Service，每个Pod将拥有独立的DNS记录。

扩容一个StatefulSet会使用下一个顺序索引创建一个新的Pod，缩容会删除索引值最高的。并且缩容任何时候只会操作一个Pod。

如何提供稳定的存储#

StatefulSet可以拥有一个或多个PVC模板，这些PVC会在创建Pod前创建出来，绑定到一个Pod实例上。

扩容的时候会创建一个Pod以及若干个PVC，删除的时候只会删除Pod。StatefulSet缩容时不会删除PVC，扩容时会重新挂上https://coub.com/stories/807189-mk

https://coub.com/stories/807189-mk

https://coub.com/stories/807026-as

https://coub.com/stories/806957-rd

https://coub.com/stories/806863-qq

https://coub.com/stories/806603-sc

https://coub.com/stories/806533-se

https://coub.com/stories/806491-rp

https://coub.com/stories/806439-ok

https://coub.com/stories/806379-ey

https://coub.com/stories/806319-cq

https://coub.com/stories/806266-cq

https://coub.com/stories/806207-rz

https://coub.com/stories/806146-dh

https://coub.com/stories/806072-jb

https://coub.com/stories/806015-zv

https://coub.com/stories/805974-so

https://coub.com/stories/805913-ff

https://coub.com/stories/805861-gc

https://coub.com/stories/805811-vv

https://coub.com/stories/805741-tb

https://coub.com/stories/805661-lx

https://coub.com/stories/805526-as

https://coub.com/stories/805435-nb

https://coub.com/stories/805382-qi

https://coub.com/stories/805325-tu

https://coub.com/stories/805270-ko

https://coub.com/stories/805180-pr

https://coub.com/stories/805129-lb

https://coub.com/stories/804968-mo

https://coub.com/stories/804901-zz

https://coub.com/stories/804834-vd

https://coub.com/stories/804780-em

https://coub.com/stories/804744-ks

https://coub.com/stories/804693-zp

https://coub.com/stories/804648-uq

https://coub.com/stories/804571-yi

https://coub.com/stories/804470-lb

https://coub.com/stories/804398-rd

https://coub.com/stories/804293-ss

https://coub.com/stories/804230-km

https://coub.com/stories/804207-wk

https://coub.com/stories/804162-bf

https://coub.com/stories/804121-nz

https://coub.com/stories/804090-wa

https://coub.com/stories/804067-nb

https://coub.com/stories/804013-sw

https://coub.com/stories/803939-ha

https://coub.com/stories/803890-ya

https://coub.com/stories/803860-np

https://coub.com/stories/803820-qy

https://coub.com/stories/803774-as

https://coub.com/stories/803739-rt

https://coub.com/stories/803702-sl

https://coub.com/stories/803657-ok

https://coub.com/stories/803593-ks

https://coub.com/stories/803554-dp

https://coub.com/stories/803517-sa

https://coub.com/stories/803464-ll

https://coub.com/stories/803413-gn

https://coub.com/stories/803367-ei

https://coub.com/stories/803327-oh

https://coub.com/stories/803288-wp

https://coub.com/stories/803252-bb

https://coub.com/stories/803214-ky

https://coub.com/stories/803168-qw

https://coub.com/stories/803657-ok

https://coub.com/stories/803593-ks

https://coub.com/stories/803554-dp

https://coub.com/stories/803517-sa

https://coub.com/stories/803464-ll

https://coub.com/stories/803413-gn

https://coub.com/stories/803367-ei

https://coub.com/stories/803327-oh

https://coub.com/stories/803288-wp

https://coub.com/stories/803252-bb

https://coub.com/stories/803214-ky

https://coub.com/stories/803168-qw

https://coub.com/stories/803128-ws

https://coub.com/stories/803070-zh

https://coub.com/stories/803024-zz

https://coub.com/stories/802966-ex

https://coub.com/stories/802915-qw

https://coub.com/stories/802876-el

https://coub.com/stories/802845-iq

https://coub.com/stories/802799-qi

https://coub.com/stories/802763-eg

https://coub.com/stories/802722-se

https://coub.com/stories/802700-sa

https://coub.com/stories/802658-wy

https://coub.com/stories/802636-pf

https://coub.com/stories/802598-vg

https://coub.com/stories/803214-ky

https://coub.com/stories/803168

https://coub.com/stories/803128

https://coub.com/stories/803070

https://coub.com/stories/803024-zz

https://coub.com/stories/802966-ex

https://coub.com/stories/802915-qw

https://coub.com/stories/802876-el

https://coub.com/stories/802845-iq

https://coub.com/stories/802799-qi

https://coub.com/stories/802763-eg

https://coub.com/stories/802722-se

https://coub.com/stories/802700-sa

https://coub.com/stories/802658-wy

https://coub.com/stories/802636-pf

https://coub.com/stories/802598-vg

https://coub.com/stories/802569-aa

https://coub.com/stories/802538-qa

https://coub.com/stories/802484-gl

https://coub.com/stories/802434-nn

https://coub.com/stories/802388-nn

https://coub.com/stories/802328-si

https://coub.com/stories/802278-zo

https://coub.com/stories/802248-sy

https://coub.com/stories/802206-se

https://coub.com/stories/802048-iq

https://coub.com/stories/801971-zr

https://coub.com/stories/801888-uq

https://coub.com/stories/801792-bj

https://coub.com/stories/801728-qo

https://coub.com/stories/801640-nn

https://coub.com/stories/801590-mk

https://coub.com/stories/801512-ea

https://coub.com/stories/802169-vf

https://coub.com/stories/801448-ku

https://coub.com/stories/801375-ow

https://coub.com/stories/801308-wm

https://coub.com/stories/801275-dn

https://coub.com/stories/801228-yr

https://coub.com/stories/801102-ph

https://coub.com/stories/801044-rh

https://coub.com/stories/800941-lp

https://coub.com/stories/800863-pj

https://coub.com/stories/800803-ui

https://coub.com/stories/800748-vt

https://coub.com/stories/800685-mc

https://coub.com/stories/800643-aa

https://coub.com/stories/800578-sq

https://coub.com/stories/800523-fk

https://coub.com/stories/800451-uv

https://coub.com/stories/800230-wu

https://coub.com/stories/800178-qj

https://coub.com/stories/800114-wa

https://coub.com/stories/800031-ca

https://coub.com/stories/799950-xa

https://coub.com/stories/799878-ec

https://coub.com/stories/799812-pp

https://coub.com/stories/799763-yy

https://coub.com/stories/799729-em

https://coub.com/stories/799540-ew

https://coub.com/stories/799320-pd

https://coub.com/stories/799261-fp

https://coub.com/stories/799216-tx

https://coub.com/stories/799152-yi

https://coub.com/stories/799088-bj

https://coub.com/stories/799034-xx

https://coub.com/stories/798969-ji

https://coub.com/stories/798922-im

https://coub.com/stories/798881-ju

https://coub.com/stories/798729-we

https://coub.com/stories/798663-uy

https://coub.com/stories/798519-oa

https://coub.com/stories/798279-hh

https://coub.com/stories/798217-yg

https://coub.com/stories/798149-mb

https://coub.com/stories/798084-me

https://coub.com/stories/798044-wa

https://coub.com/stories/797986-mk

https://coub.com/stories/797914-gu

https://coub.com/stories/797756-el

https://coub.com/stories/797585-ka

https://coub.com/stories/797540-me

https://coub.com/stories/797452-iq

https://coub.com/stories/797250-pb

https://coub.com/stories/797165-um

https://coub.com/stories/796997-we

https://coub.com/stories/796904-lp

https://coub.com/stories/796813-lt

https://coub.com/stories/796747-nj

https://coub.com/stories/796684-ko

https://coub.com/stories/796624-we

https://coub.com/stories/796481-ny

https://coub.com/stories/796415-wa

https://coub.com/stories/796347-nq

https://coub.com/stories/796292-zt

https://coub.com/stories/796233-ti

https://coub.com/stories/796156-es

https://coub.com/stories/796052-np

https://coub.com/stories/795902-jj

https://coub.com/stories/795804-yn

https://coub.com/stories/795609-xv

https://coub.com/stories/795486-bj

https://coub.com/stories/795254-mj

https://coub.com/stories/795199-go

https://coub.com/stories/795046-pa

https://coub.com/stories/794945-bu

https://coub.com/stories/794857-mu

https://coub.com/stories/794792-ww

https://coub.com/stories/794747-oo

https://coub.com/stories/794510-bx

https://coub.com/stories/794444-wi

https://coub.com/stories/794371-ia

https://coub.com/stories/794309-ti

https://coub.com/stories/794255-hw

https://coub.com/stories/794206-ss

https://coub.com/stories/794161-db

https://coub.com/stories/794100-am

https://coub.com/stories/793887-ow

https://coub.com/stories/793721-kk

https://coub.com/stories/793611-os

https://coub.com/stories/793566-kw

https://coub.com/stories/793483-ln

https://coub.com/stories/793431-tl

https://coub.com/stories/793353-hv

https://coub.com/stories/793299-xx

https://coub.com/stories/793238-ju

https://coub.com/stories/793164-hv

https://coub.com/stories/793129-wa

https://coub.com/stories/793085-cn

https://coub.com/stories/793049-eo

https://coub.com/stories/792932-os

https://coub.com/stories/792878-ku

https://coub.com/stories/792819-ow

https://coub.com/stories/792684-ke

https://coub.com/stories/792443-nr

https://coub.com/stories/792270-qg

https://coub.com/stories/792178-cq

https://coub.com/stories/792155-aa

https://coub.com/stories/792138-lw

https://coub.com/stories/792077-ei

https://coub.com/stories/792049-go

https://coub.com/stories/792020-sy

https://coub.com/stories/791993-dn

https://coub.com/stories/791971-oe

https://coub.com/stories/791940-sk

https://coub.com/stories/791911-yf

https://coub.com/stories/791879-yy

https://coub.com/stories/791851-yk

https://coub.com/stories/791817-hr

https://coub.com/stories/791790-fx

https://coub.com/stories/791755-xx

https://coub.com/stories/791705-zz

https://coub.com/stories/791673-bz

https://coub.com/stories/791640-zj

https://coub.com/stories/791613-sa

https://coub.com/stories/791575-qs

https://coub.com/stories/791558-zv

https://coub.com/stories/791543-eb

https://coub.com/stories/791522-ou

https://coub.com/stories/791500-xh

https://coub.com/stories/791425-si

https://coub.com/stories/791385-vh

https://coub.com/stories/791359-wg

https://coub.com/stories/791315-xr

https://coub.com/stories/791278-fb